impl(generator): push and pop deprecated pragma when needed

[scotthart]

In a previous PR, the disable_deprecations_warnings.inc was added to services that were deprecated. This PR also adds this include file when the service contains methods that are marked as deprecated. As the disable_deprecations_warnings.inc includes a pragma push, the corresponding pragma pop needed to be added, which this PR adds.

This was tested with both protobuf v28.3 and protobuf v29.0-rc3 and in both cases the [[deprecated]] present in the generated protobuf messages no longer results in a compilation error.

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This change is 

[codecov]

Codecov Report

Attention: Patch coverage is 63.63636% with 24 lines in your changes missing coverage. Please review.

Project coverage is 92.99%. Comparing base (8e7038e) to head (8e219d8).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
generator/internal/service_code_generator.cc	77.77%	4 Missing ⚠️
...nerator/internal/connection_impl_rest_generator.cc	0.00%	2 Missing ⚠️
generator/internal/connection_rest_generator.cc	0.00%	2 Missing ⚠️
...rator/internal/logging_decorator_rest_generator.cc	0.00%	2 Missing ⚠️
...ator/internal/metadata_decorator_rest_generator.cc	0.00%	2 Missing ⚠️
...erator/internal/round_robin_decorator_generator.cc	0.00%	2 Missing ⚠️
generator/internal/stub_factory_rest_generator.cc	0.00%	2 Missing ⚠️
generator/internal/stub_rest_generator.cc	0.00%	2 Missing ⚠️
generator/internal/forwarding_client_generator.cc	0.00%	1 Missing ⚠️
...erator/internal/forwarding_connection_generator.cc	0.00%	1 Missing ⚠️
... and 4 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #14852      +/-   ##
==========================================
- Coverage   93.00%   92.99%   -0.02%     
==========================================
  Files        2351     2351              
  Lines      209479   209543      +64     
==========================================
+ Hits       194818   194856      +38     
- Misses      14661    14687      +26     

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[dbolduc]

On second thought, this is not the place to push/pop. We should only push/pop around where we include the protobuf generated code.

Otherwise we are silencing the deprecation warnings for our deprecated client classes. We don't want that. We want customers to see those warnings.