Revert "chore(llmobs): add language tag to span events [backport 2.12]"

[sabrenner]

Reverts #10703

Checklist

• PR author has checked that all the criteria below are met
• The PR description includes an overview of the change
• The PR description articulates the motivation for the change
• The change includes tests OR the PR description describes a testing strategy
• The PR description notes risks associated with the change, if any
• Newly-added code is easy to change
• The change follows the library release note guidelines
• The change includes or references documentation updates if necessary
• Backport labels are set (if applicable)

Reviewer Checklist

• Reviewer has checked that all the criteria below are met
• Title is accurate
• All changes are related to the pull request's stated goal
• Avoids breaking API changes
• Testing strategy adequately addresses listed risks
• Newly-added code is easy to change
• Release note makes sense to a user of the library
• If necessary, author has acknowledged and discussed the performance implications of this PR as reported in the benchmarks PR comment
• Backport labels are set in a manner that is consistent with the release branch maintenance policy

[datadog-dd-trace-py-rkomorn]

Datadog Report

Branch report: revert-10703-backport-10681-to-2.12
Commit report: 02e352b
Test service: dd-trace-py

✅ 0 Failed, 767 Passed, 40266 Skipped, 32m 23.21s Total duration (1h 57m 36.45s time saved)

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-09-30 13:42:54

Comparing candidate commit 02e352b in PR branch revert-10703-backport-10681-to-2.12 with baseline commit db5721c in branch 2.12.

Found 0 performance improvements and 0 performance regressions! Performance is the same for 353 metrics, 47 unstable metrics.