fix(gapic-common): ignore inherited Service constants in normalize_service

[linyiru]

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closes: #70

Summary

Gapic::LoggingConcerns.normalize_service looks up the Service constant with const_defined?'s default inherit: true. Generated REST stubs have no sibling Service, so the lookup walks up to Object. If the application defines a top-level ::Service, it is treated as a gRPC Service and service_name is called on it, raising NoMethodError during client construction.

gRPC transports are unaffected because they do define a local Service.

Change

Look up Service and Rest with inherit: false so only constants defined on the enclosing module are considered.

Tests

On starship (Ruby 3.4.10):

• toys test: 316 runs, 948 assertions, 0 failures, 0 errors
• bundle exec rubocop lib: 42 files, no offenses
• bundle exec ruby -Ilib:test test/gapic/logging_concerns_test.rb: 10 runs, 12 assertions, 0 failures

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[linyiru]

CLA is signed and green now.

The CI workflow run is sitting in action_required — as a first-time contributor from a fork, it needs a maintainer to click "Approve and run workflows" before anything starts. Could someone kick it off, and take a look when you get a chance?

Ran the suite locally in the meantime (Ruby 3.3.10, macOS):

• gapic-common tests: 316 runs, 948 assertions, 0 failures, 0 errors, 1 skip
• rubocop: 44 files inspected, no offenses

Happy to adjust anything.