[CODE HEALTH] Fix clang-tidy param-not-moved in otlp grpc exporters

[dbarker]

Contributes to #2053

Changes

Fixes the following warnings:

Warnings by clang-tidy Check - Click to expand

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cppcoreguidelines-rvalue-reference-param-not-moved (12 warnings)

File	Line	Message
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_client.cc	529	rvalue reference parameter 'context' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_client.cc	530	rvalue reference parameter '' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_client.cc	531	rvalue reference parameter 'request' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_client.cc	539	rvalue reference parameter 'context' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_client.cc	540	rvalue reference parameter '' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_client.cc	541	rvalue reference parameter 'request' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_client.cc	549	rvalue reference parameter 'context' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_client.cc	550	rvalue reference parameter '' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_client.cc	551	rvalue reference parameter 'request' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_exporter.cc	156	rvalue reference parameter '' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_log_record_exporter.cc	158	rvalue reference parameter '' is never moved from inside the function body
opentelemetry-cpp/exporters/otlp/src/otlp_grpc_metric_exporter.cc	168	rvalue reference parameter '' is never moved from inside the function body

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For significant contributions please make sure you have completed the following items:

• CHANGELOG.md updated for non-trivial changes
• Unit tests have been added
• Changes in public API reviewed

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.12%. Comparing base (e8c5ee2) to head (626f4d5).

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #3956   +/-   ##
=======================================
  Coverage   90.12%   90.12%           
=======================================
  Files         227      227           
  Lines        7261     7261           
=======================================
  Hits         6543     6543           
  Misses        718      718           

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