This repo does not have markdown linting, causing this rule to be
triggered often during review.

I don't personally believe multi-line sentences degrade our
documentation quality. Removing this reduces review noise.

.codeclimate.yml and .mdlrc were added in 2018 for GitLab's legacy
Code Climate-based Code Quality feature. Current CI uses common-ci-tasks
templates with no code_quality job, so nothing reads these files. Also
drop the stale "validated by markdownlint" note from the Duo review
instructions, since no such linter runs.

chore(duo): remove .md rule that sentences must start on new line

See merge request !574

Merged-by: Matias Alvarez <malvarez@gitlab.com>
Approved-by: Matias Alvarez <malvarez@gitlab.com>
Co-authored-by: Luke Hollinda <lhollinda@gitlab.com>

chore: remove orphaned Code Climate and markdownlint config

See merge request !575

Merged-by: Matias Alvarez <malvarez@gitlab.com>
Approved-by: Matias Alvarez <malvarez@gitlab.com>
Co-authored-by: Luke Hollinda <lhollinda@gitlab.com>

An invalid GITLAB_TRACING value (for example the legacy v1
opentracing:// connection string that Runway injects by default) was
silently ignored, so the OTLP exporter fell back to its built-in
default of https://localhost:4318 and export failed with connection
refused, with no hint as to why.

Log a warning from NewWithConfig when the variable is set but cannot
be parsed. The raw value is not logged because header_* query
parameters may carry credentials. ParseTracingConfig and
ParseTracingConfigFromEnv remain silent so callers using them as pure
parsers are unaffected.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Combine the warns-when-invalid and does-not-warn cases into a single
table-driven test covering all permutations of the env var: unset,
empty, each valid scheme, and each invalid form.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

fix(v2/trace): warn when GITLAB_TRACING is set but not parseable

See merge request !576

Merged-by: Matias Alvarez <malvarez@gitlab.com>
Approved-by: Sahand Abbasi <sabbasi@gitlab.com>
Approved-by: Matias Alvarez <malvarez@gitlab.com>
Reviewed-by: GitLab Duo <gitlab-duo@gitlab.com>
Co-authored-by: e_forbes <eforbes@gitlab.com>