Add missing proto to thrift enum mappings and unit tests for EnumMapper

[natemort]

What changed?
Add a suite of tests that will automatically fail if new enum types are added in IDL but the mappers aren't updated. This was done in a few ways:

• For enums that have mappers both directions, we roundtrip all thrift values and assert that they're equal.
• For enums that are identical across thrift/proto, we generate a mapping based on the value names and assert that the mapper matches it.
• For enums that aren't identical, we explicitly assert that our mapping contains all values.

Why?

• Increase test coverage and GRPC compatibility

How did you test it?

• Unit tests

Potential risks

Release notes

Documentation Changes

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

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Additional details and impacted files

Files with missing lines	Coverage Δ
...dence/internal/compatibility/proto/EnumMapper.java	75.70% <ø> (ø)
...ence/internal/compatibility/thrift/EnumMapper.java	71.87% <100.00%> (ø)

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[coveralls]

Pull Request Test Coverage Report for Build 2541

Details

• 2 of 2 (100.0%) changed or added relevant lines in 1 file are covered.
• 8 unchanged lines in 4 files lost coverage.
• Overall coverage increased (+0.8%) to 66.108%

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Files with Coverage Reduction	New Missed Lines	%
src/main/java/com/uber/cadence/internal/sync/WorkflowThreadContext.java	1	81.58%
src/main/java/com/uber/cadence/internal/sync/CancellationScopeImpl.java	1	92.65%
src/main/java/com/uber/cadence/internal/worker/Poller.java	1	78.13%
src/main/java/com/uber/cadence/internal/replay/ReplayDecider.java	5	80.27%

Totals
Change from base Build 2537:	0.8%
Covered Lines:	12893
Relevant Lines:	19503

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💛 - Coveralls