Add test utility for error-specific RemoteException and SerializableError

[mpritham]

Before this PR

Previously devs would mock interactions with Dialogue clients that threw a RemoteException by creating a Mockito mock returning a constructed RemoteException. Now, clients throw subclasses of RemoteException. It is not possible to construct these error-specific RemoteExceptions because the error's SerializableError constructor (a required parameter when constructing the RemoteException subclass) is package private. I'd like this to remain package-private: devs should not be constructing these errors in their production code. Still, there should be an easy way for folks to construct these error-specific RemoteExceptions for use in unit tests.

After this PR

For each error, generate a test utility class that is able to construct error specific RemoteExceptions and SerializableErrors.

==COMMIT_MSG==
Add test utility for error-specific RemoteException and SerializableError
==COMMIT_MSG==

Possible downsides?

I would like folks to only use this in tests. I've named the class TestUtility and provided a JavaDoc telling folks to only use this in tests. Still, it's possible for folks to construct and throw these Conjure-generated exceptions in their code if they really wanted to.

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Description

Add test utility for error-specific RemoteException and SerializableError

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[aldexis]

If we want to make sure this doesn't get used outside of tests, we could go one step further, and create a separate xxx-test-utilities library, but this seems much more involved, so this feels reasonable to me

[aldexis]

Another approach would be to have one TestUtility class per XErrors class. Makes the "Test" part of the name a bit more prominent.
I don't have strong feelings either way.

[mpritham]

Think I'll merge with the current state. With the approach where we have one test utility, I think we'd have to name each method like createXSerializableError. I think it'd be slightly easier to search for usages of places folks have created these errors by having all the constructors have the same name.

Invalidated by push of 5f2df76

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💡 Improvements

• Add test utility for error-specific RemoteException and SerializableError (#2718)

[autorelease3]

Released 8.64.0