Remove is-gen-fn dependency

[yelworc]

The is-gen-fn package causes a DeprecationWarning with Node 16:

 Uncaught DeprecationWarning: Invalid 'main' field in '/home/crowley/work/uniq/uniq-conferencier/node_modules/is-gen-fn/package.json' of 'yes'. Please either fix that or report it to the module author
  at tryPackage (node:internal/modules/cjs/loader:359:15)
  […]

Since it is fairly trivial, just include the generator function check here.

[yelworc]

Ah, I did glance at the open issues, but didn't look closely at the open PRs! Alright, feel free to close this, then (unless you maybe want to merge it as a temporary fix, since it could be released as a patch version until #128 lands).

[Aldekein]

The DeprecationWarning: Invalid 'main' field bugs me too. Its source is is-gen-fn@0.0.1 in dependencies of joi-router.

[flofehrenbacher-sz]

Any updates regarding this PR? Would also love to use it without the deprecation warning

[3imed-jaberi]

Updates: For now, you can use @koa-better-modules/joi-router which contains all the changes that must be in v9.x.x until I can publish the next official release under @koa/joi-router (expected in the coming few weeks).

Check 👀

[hckhanh]

Hi @3imed-jaberi, is there anything new for this PR, I created another PR for this: #137

[jackykwan-eventx]

@3imed-jaberi hello, is this package currently still under maintenence ? seems like no updates for a long period of time

[3imed-jaberi]

Hey Guys, next week we will publish the latest version (including the latest fixed) under @koa/joi-router. If you don't like to wait for next week, you can use the latest version by installing @koa-better-modules/joi-router

More details here