Fix CI lint error from new stable toolchain v1.83

[lalitb]

Changes

Errors - https://github.com/open-telemetry/opentelemetry-rust/actions/runs/12108882297/job/33757381774?pr=2369

It seems we should have a lint check for beta toolchain, else CI may fail for new stable release as this time.

Summary of changes required for rust toolchain v1.83 (released on 29th Nov)

• Remove explicit lifetime annotation if not required, to fix errors like:

error: the following explicit lifetimes could be elided: 'a
  --> opentelemetry/src/metrics/instruments/mod.rs:116:6
   |
116 | impl<'a> HistogramBuilder<'a, Histogram<f64>> {

• empty lines after doc-comments, to fix errors like:

error: empty lines after doc comment
  --> opentelemetry/src/global/internal_logging.rs:6:1
   |
6  | / ///
7  | |
8  | | /// Macro for logging informational messages in OpenTelemetry.
9  | | ///

Also this requires fixing the sem-conv jina file, to remove empty line during doc-generation.

Merge requirement checklist

• CONTRIBUTING guidelines followed
• Unit tests added/updated (if applicable)
• Appropriate CHANGELOG.md files updated for non-trivial, user-facing changes
• Changes in public API reviewed (if applicable)

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 79.5%. Comparing base (e0159ad) to head (ff6d125).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #2370     +/-   ##
=======================================
- Coverage   79.5%   79.5%   -0.1%     
=======================================
  Files        123     123             
  Lines      21492   21492             
=======================================
- Hits       17094   17092      -2     
- Misses      4398    4400      +2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.