[CODE HEALTH] clang-tidy warnings in baggage.h

[dbarker]

clang-tidy reports the following warnings in baggage.h

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opentelemetry-cpp/api/include/opentelemetry/baggage/baggage.h (3 warnings)

Line	Check	Message
238	cppcoreguidelines-narrowing-conversions	narrowing conversion from 'int' to signed type 'char' is implementation-defined
239	cppcoreguidelines-narrowing-conversions	narrowing conversion from 'int' to signed type 'char' is implementation-defined
270	cppcoreguidelines-narrowing-conversions	narrowing conversion from 'int' to signed type 'char' is implementation-defined

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To reproduce locally run the following in the development container:

export CXX_STANDARD=14
./ci/do_ci.sh cmake.clang_tidy.test

The markdown report with unique errors can be generated locally after building with the ci/create_clang_tidy_report.py script.

[github-actions]

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