Convert :workflow-core to kmp

[bnvinay92]

Rundown:

• Changed the repositoriesMode setting from RepositoriesMode.FAIL_ON_PROJECT_REPOS to RepositoriesMode.PREFER_PROJECT. The multiplatform gradle plugin implicitly adds an ivy() repo to download the kotlin native compiler. Looking for a workaround for this, or at least some way to allow only multiplatform modules on preferring project repos.
• WorkflowIdentifier was using type: KAnnotatedElement to represent either a KClass or a KType. Explicitly introduced a sealed class WorkflowIdentifierType to emulate this. Equality is now based on the serialized version of this sealed class, which allows save and restore without reflection. KClasses are lost after restoration but since identifiers are only used for comparison in tests this shouldn't break anything.
• org.jetbrains.kotlinx:kotlinx-coroutines-test:1.5.1 only ships a jvm artifact so bumped only this test dependency in commonTest to 1.6.1 (which ships artifacts for all platforms)

[RBusarow]

Thanks for this! It looks great!

I ran this branch's snapshot through the CI on our main project and everything's green. So, as soon as we've added some KDoc to WorkflowIdentifierType, I can approve.

[RBusarow]

No big deal.

[bnvinay92]

Thanks for this! It looks great!

I ran this branch's snapshot through the CI on our main project and everything's green. So, as soon as we've added some KDoc to WorkflowIdentifierType, I can approve.

Thanks. Added KDoc and removed the redundant dependency here.

[RBusarow]

Great, thanks!

[steve-the-edwards]

🥳