profiles: publish alpha release of data model and OTLP exporter

[jhalliday]

Following the alpha release of the profiles signal spec it makes sense to ship some initial utility code to assist Java users adopting the spec. A data model and wire message encoders are included.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.82%. Comparing base (c6a6358) to head (a16c754).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #8351      +/-   ##
============================================
+ Coverage     90.31%   90.82%   +0.50%     
- Complexity     7725     7928     +203     
============================================
  Files           850      895      +45     
  Lines         23259    23872     +613     
  Branches       2364     2378      +14     
============================================
+ Hits          21007    21682     +675     
+ Misses         1528     1446      -82     
- Partials        724      744      +20     

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[jack-berg]

Looks good to me. I ran ./gradlew publishToMavenLocal to verify artifact names are correct and include the -alpha suffix.

Take a look @open-telemetry/java-approvers