change hibernate-validator and expressly to test scope

[stevehu]

What would you like to be added:
Those two dependencies are not needed in runtime and they are only used by the test cases in api and impl modules.

Why is this needed:
By moving the two dependencies to the test scope, we can minimize the dependency for api and impl modules.

If this is agreed, I can submit a PR to resolve it. Thanks a lot for providing the Java sdk and reference implementation.

[fjtirado]

These dependencies are "needed" (they can be replaced by a diferent implementation of Jakarta Validation API) at runtime by any project using the SDK. When a workflow is read into memory, the jakarta validation annotation requires an underlying validation runtime to be present there.
However, these dependencies are not required at compilation time, so a PR is indeed needed to change the scope to runtime. I added comments to the PR you opened.

[stevehu]

@fjtirado Thanks a lot for the clarification. I realized that Jakarta Validation API doesn't have its implementation and it requires the hibernate-validator as it is the only reference implementation available. Given that, it is a good idea to keep the current dependency. I will close the PR.