Add support for RxJava 3 reactive types

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[x] Steps to reproduce provided
[x] Stacktrace (if present) provided
[ ] Example that reproduces the problem uploaded to Github
[x] Full description of the issue provided (see below)

Steps to Reproduce

Implement a cache bean returning a Single (RxJava3) like so
```
import io.reactivex.rxjava3.core.Single;
...
```

@Cacheable public Single getDataById(String id) { }

2. Setup your caching (I'm using redis) as usual
3. Request the method to store data in cache

### Expected Behaviour

I expect the data to be stored in cache

### Actual Behaviour

A exception is thrown:

`io.micronaut.core.async.publisher.CompletableFuturePublisher cannot be cast to class SomePoJo (io.micronaut.core.async.publisher.CompletableFuturePublisher and SomePoJo are in unnamed module of loader 'app')"`

16:52:38.075 [io-executor-thread-1:SHDZEFFDS] ERROR i.m.h.s.netty.RoutingInBoundHandler - Unexpected error occurred: class io.micronaut.core.async.publisher.CompletableFuturePublisher cannot be cast to class de.addmore.business.cvpn.repository.ntas.model.GroupVpnData (io.micronaut.core.async.publisher.CompletableFuturePublisher and de.addmore.business.cvpn.repository.ntas.model.GroupVpnData are in unnamed module of loader 'app') java.lang.ClassCastException: class io.micronaut.core.async.publisher.CompletableFuturePublisher cannot be cast to class de.addmore.business.cvpn.repository.ntas.model.GroupVpnData (io.micronaut.core.async.publisher.CompletableFuturePublisher and de.addmore.business.cvpn.repository.ntas.model.GroupVpnData are in unnamed module of loader 'app') at io.reactivex.rxjava3.internal.operators.single.SingleMap$MapSingleObserver.onSuccess(SingleMap.java:58) at io.micronaut.rxjava3.instrument.RxInstrumentedSingleObserver.onSuccess(RxInstrumentedSingleObserver.java:65) at io.reactivex.rxjava3.internal.operators.single.SingleResumeNext$ResumeMainSingleObserver.onSuccess(SingleResumeNext.java:65) at io.micronaut.rxjava3.instrument.RxInstrumentedSingleObserver.onSuccess(RxInstrumentedSingleObserver.java:65) at io.reactivex.rxjava3.internal.operators.single.SingleJust.subscribeActual(SingleJust.java:30) at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4813) at io.micronaut.rxjava3.instrument.RxInstrumentedSingle.subscribeActual(RxInstrumentedSingle.java:52) at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4813) at io.reactivex.rxjava3.internal.operators.single.SingleResumeNext.subscribeActual(SingleResumeNext.java:39) at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4813) at io.micronaut.rxjava3.instrument.RxInstrumentedSingle.subscribeActual(RxInstrumentedSingle.java:52) at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4813) at io.reactivex.rxjava3.internal.operators.single.SingleMap.subscribeActual(SingleMap.java:35) at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4813) at io.micronaut.rxjava3.instrument.RxInstrumentedSingle.subscribeActual(RxInstrumentedSingle.java:52) at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4813) at io.reactivex.rxjava3.internal.operators.single.SingleMap.subscribeActual(SingleMap.java:35) at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4813) at io.micronaut.rxjava3.instrument.RxInstrumentedSingle.subscribeActual(RxInstrumentedSingle.java:52) at io.reactivex.rxjava3.core.Single.subscribe(Single.java:4813) at hu.akarnokd.rxjava3.bridge.SingleV3toV2.subscribeActual(SingleV3toV2.java:32) at io.reactivex.Single.subscribe(Single.java:3603) at io.micronaut.reactive.rxjava2.RxInstrumentedSingle.subscribeActual(RxInstrumentedSingle.java:52) at io.reactivex.Single.subscribe(Single.java:3603) at io.reactivex.internal.operators.maybe.MaybeFromSingle.subscribeActual(MaybeFromSingle.java:41) at io.reactivex.Maybe.subscribe(Maybe.java:4290) at io.reactivex.internal.operators.maybe.MaybeSwitchIfEmptySingle.subscribeActual(MaybeSwitchIfEmptySingle.java:45) at io.reactivex.Single.subscribe(Single.java:3603) at io.reactivex.internal.operators.single.SingleMap.subscribeActual(SingleMap.java:34) at io.reactivex.Single.subscribe(Single.java:3603) at io.micronaut.reactive.rxjava2.RxInstrumentedSingle.subscribeActual(RxInstrumentedSingle.java:52) at io.reactivex.Single.subscribe(Single.java:3603) at io.reactivex.internal.operators.single.SingleToFlowable.subscribeActual(SingleToFlowable.java:37) at io.reactivex.Flowable.subscribe(Flowable.java:14918) at io.reactivex.Flowable.subscribe(Flowable.java:14865) at io.micronaut.reactive.rxjava2.RxInstrumentedFlowable.subscribeActual(RxInstrumentedFlowable.java:57) at io.reactivex.Flowable.subscribe(Flowable.java:14918) at io.reactivex.Flowable.subscribe(Flowable.java:14865) at io.reactivex.internal.operators.flowable.FlowableDefer.subscribeActual(FlowableDefer.java:42) at io.reactivex.Flowable.subscribe(Flowable.java:14918) at io.reactivex.Flowable.subscribe(Flowable.java:14865) at io.micronaut.reactive.rxjava2.RxInstrumentedFlowable.subscribeActual(RxInstrumentedFlowable.java:57) at io.reactivex.Flowable.subscribe(Flowable.java:14918) at io.reactivex.Flowable.subscribe(Flowable.java:14865) at io.reactivex.internal.operators.flowable.FlowableSubscribeOn$SubscribeOnSubscriber.run(FlowableSubscribeOn.java:82) at io.reactivex.internal.schedulers.ExecutorScheduler$ExecutorWorker$BooleanRunnable.run(ExecutorScheduler.java:288) at io.reactivex.internal.schedulers.ExecutorScheduler$ExecutorWorker.run(ExecutorScheduler.java:253) at io.micronaut.scheduling.instrument.InvocationInstrumenterWrappedRunnable.run(InvocationInstrumenterWrappedRunnable.java:47) at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130) at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630) at java.base/java.lang.Thread.run(Thread.java:832)



A RxJava 2 Single works fine.

### Environment Information

- **Operating System**: Win 10
- **Micronaut Version:** 2.1.4 & 2.2.0
- **JDK Version:** JDK 15

micronaut-projects / micronaut-cache

Add support for RxJava 3 reactive types #254

Task List

Steps to Reproduce