Avoid example redefinition warning in test suite

[p-datadog]

What does this PR do?

Refactors the examples to avoid this warning:

WARNING: Shared example group 'a binary setting with' has been previously defined at:
  /home/w/apps/dd-trace-rb/spec/datadog/core/configuration/settings_spec.rb:12
...and you are now defining it at:
  /home/w/apps/dd-trace-rb/spec/datadog/core/configuration/settings_spec.rb:12

Motivation:

Warning-clean test suite

Change log entry
None

Additional Notes:
N/A

How to test the change?
Tested manually by running the relevant examples:

rspec spec/datadog/core/configuration/settings_spec.rb spec/datadog/tracing/configuration/settings_spec.rb

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.74%. Comparing base (b9e1364) to head (c389d79).
Report is 8 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4612      +/-   ##
==========================================
- Coverage   97.74%   97.74%   -0.01%     
==========================================
  Files        1412     1413       +1     
  Lines       86256    86170      -86     
  Branches     4354     4357       +3     
==========================================
- Hits        84315    84224      -91     
- Misses       1941     1946       +5     

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[datadog-datadog-prod-us1]

Datadog Report

Branch report: avoid-example-redef
Commit report: c389d79
Test service: dd-trace-rb

✅ 0 Failed, 20987 Passed, 1376 Skipped, 3m 36.8s Total Time

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-04-29 12:29:23

Comparing candidate commit c389d79 in PR branch avoid-example-redef with baseline commit b9e1364 in branch master.

Found 2 performance improvements and 0 performance regressions! Performance is the same for 29 metrics, 2 unstable metrics.

scenario:tracing - 100 span trace - no writer

• 🟩 throughput [+16.955op/s; +17.396op/s] or [+5.472%; +5.614%]

scenario:tracing - Propagation - Trace Context

• 🟩 throughput [+3463.860op/s; +3560.266op/s] or [+10.275%; +10.561%]

[Strech]

👍🏼