Support Async Lifecycles

[0xTim]

These changes are now available in 4.11.0

Support Vapor's async LifecycleHandler functions. This allows users to avoid calling .wait() when shutting down their Vapor apps, which can cause issues, for example, with trying to install a new concurrency executor.

This also updates the supported Swift version to 5.8

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 48.00000% with 26 lines in your changes are missing coverage. Please review.

Project coverage is 52.88%. Comparing base (9e42dea) to head (13da97b). Report is 2 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #214 +/- ## ========================================== - Coverage 55.58% 52.88% -2.71% ========================================== Files 11 11 Lines 412 399 -13 ========================================== - Hits 229 211 -18 - Misses 183 188 +5 ``` | [Files](https://app.codecov.io/gh/vapor/redis/pull/214?dropdown=coverage&src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vapor) | Coverage Δ | | |---|---|---| | [Sources/Redis/Application.Redis+PubSub.swift](https://app.codecov.io/gh/vapor/redis/pull/214?src=pr&el=tree&filepath=Sources%2FRedis%2FApplication.Redis%2BPubSub.swift&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vapor#diff-U291cmNlcy9SZWRpcy9BcHBsaWNhdGlvbi5SZWRpcytQdWJTdWIuc3dpZnQ=) | `0.00% <ø> (ø)` | | | [Sources/Redis/Redis+Sessions.swift](https://app.codecov.io/gh/vapor/redis/pull/214?src=pr&el=tree&filepath=Sources%2FRedis%2FRedis%2BSessions.swift&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vapor#diff-U291cmNlcy9SZWRpcy9SZWRpcytTZXNzaW9ucy5zd2lmdA==) | `86.84% <ø> (ø)` | | | [Sources/Redis/RedisConfiguration.swift](https://app.codecov.io/gh/vapor/redis/pull/214?src=pr&el=tree&filepath=Sources%2FRedis%2FRedisConfiguration.swift&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vapor#diff-U291cmNlcy9SZWRpcy9SZWRpc0NvbmZpZ3VyYXRpb24uc3dpZnQ=) | `92.30% <ø> (-0.34%)` | :arrow_down: | | [Sources/Redis/RedisID.swift](https://app.codecov.io/gh/vapor/redis/pull/214?src=pr&el=tree&filepath=Sources%2FRedis%2FRedisID.swift&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vapor#diff-U291cmNlcy9SZWRpcy9SZWRpc0lELnN3aWZ0) | `62.50% <ø> (ø)` | | | [Sources/Redis/Redis+Cache.swift](https://app.codecov.io/gh/vapor/redis/pull/214?src=pr&el=tree&filepath=Sources%2FRedis%2FRedis%2BCache.swift&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vapor#diff-U291cmNlcy9SZWRpcy9SZWRpcytDYWNoZS5zd2lmdA==) | `71.87% <85.71%> (-3.99%)` | :arrow_down: | | [Sources/Redis/RedisStorage.swift](https://app.codecov.io/gh/vapor/redis/pull/214?src=pr&el=tree&filepath=Sources%2FRedis%2FRedisStorage.swift&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vapor#diff-U291cmNlcy9SZWRpcy9SZWRpc1N0b3JhZ2Uuc3dpZnQ=) | `60.81% <41.86%> (-13.88%)` | :arrow_down: | ... and [2 files with indirect coverage changes](https://app.codecov.io/gh/vapor/redis/pull/214/indirect-changes?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=vapor)

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