chore: reconcile lambda runtime support

[ava-silver]

What does this PR do?

Stops accepting nodejs12.x, python2.7, and python3.6 as supported tracer runtimes. They now follow the macro's existing unsupported-runtime path.

Updates affected tests to use supported runtimes.

Motivation

Align runtime acceptance with AWS function-update lifecycle. Keep runtimes supported while AWS still permits customers to update their functions.

Testing Guidelines

No manual validation.

Additional Notes

nodejs14.x, nodejs16.x, python3.7, java8, and java8.al2 remain supported. This PR is stacked on #269 and does not add generated tracer or Extension defaults.

Types of changes

• Bug fix
• New feature
• Breaking change
• Misc (docs, refactoring, dependency upgrade, etc.)

Check all that apply

• This PR's description is comprehensive
• This PR contains breaking changes that are documented in the description
• This PR introduces new APIs or parameters that are documented and unlikely to change in the foreseeable future
• This PR impacts documentation, and it has been updated (or a ticket has been logged)
• This PR's changes are covered by the automated tests
• This PR collects user input/sensitive content into Datadog

[ava-silver]

• chore: reconcile lambda runtime support #270 👈 (View in Graphite)
• chore: prepare lambda layer catalog #269
• main

This stack of pull requests is managed by Graphite. Learn more about stacking.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 86.74%. Comparing base (95270d4) to head (a58bdf1).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #270      +/-   ##
==========================================
- Coverage   86.83%   86.74%   -0.10%     
==========================================
  Files          19       19              
  Lines        1762     1750      -12     
  Branches      352      352              
==========================================
- Hits         1530     1518      -12     
  Misses        231      231              
  Partials        1        1              

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[avangelillo]

I don't think we should remove this, AWS won't block function update until March 3 2027. Same with node 16 and python 3.7

https://docs.aws.amazon.com/lambda/latest/dg/lambda-runtimes.html

[ava-silver]

good call, sounds like it may be worth adding aws lifecycle data to the checks here beyond just github releases -- I'll confirm the logic/full list of what we support with apm serverless before moving forward here

[ava-silver]

okay i've removed only the ones that are past the update block date -- so up through python 3.6 and through node 14