chore: move xray propagators back to contrib

[pichlermarc]

Which problem is this PR solving?

• the spec prohibits us from hosting vendor propagators in the core repo. From the spec:

Additional Propagators implementing vendor-specific protocols such as AWS
X-Ray trace header protocol MUST NOT be maintained or distributed as part of
the Core OpenTelemetry repositories.

Short description of the changes

• moves the xray and xray lambda propagators back to contrib
• adapts dependencies and lifecycle scripts to contrib repo.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.77%. Comparing base (dfb2dff) to head (1dda06f).
Report is 226 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2411      +/-   ##
==========================================
- Coverage   90.97%   90.77%   -0.20%     
==========================================
  Files         146      158      +12     
  Lines        7492     7722     +230     
  Branches     1502     1596      +94     
==========================================
+ Hits         6816     7010     +194     
- Misses        676      712      +36     

Files with missing lines	Coverage Δ
...tor-aws-xray-lambda/src/AWSXRayLambdaPropagator.ts	100.00% <100.00%> (ø)
...ators/propagator-aws-xray/src/AWSXRayPropagator.ts	100.00% <100.00%> (ø)

... and 76 files with indirect coverage changes