`ExtensionContext` does not enforce preconditions for `publishFile()` and `publishDirectory()`

[sbrannen]

ExtensionContext.publishFile() and ExtensionContext.publishDirectory() both document that the supplied file or directory name must not be null or blank.

However, AbstractExtensionContext (which is the implementation of the ExtensionContext interface) does not check if the supplied name is blank.

We should therefore revise the precondition checks to comply with the documented behavior.

[Woongi9]

I create fix #4901 PR with tests👍

[mehulimukherjee]

Hi @sbrannen , could you please assign this to me?
Thanks & Regards,
Mehuli