Add scala3 source detection

[kanderson250]

Minor change to add a bit of detection for apps using scala 3.

This has some significant limitations:

• This feature detects only the major version. Scala 3 removed the API methods exposing the version number, so we no longer can read that in-code. An app running with Scala 3.3.4 and Scala 3.5.0 will both report the same supportability metric, Supportability/SourceVersion/scala/3.x.
• (Existing limitation with scala <=2.13 detection): This feature only detects scala libraries present on the system classloader. This means that apps launched with the sbt and scala CLIs, which load core scala classes into special Scala Class Loaders, will not capture this metric. Apps launched with java, or any other CLI that doesn't treat scala libraries special, will be ok.

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 50.00000% with 5 lines in your changes missing coverage. Please review.

Project coverage is 70.72%. Comparing base (925da72) to head (bcf321e).
Report is 5 commits behind head on main.

Files with missing lines	Patch %	Lines
...newrelic/agent/language/SourceLibraryDetector.java	50.00%	5 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #2172   +/-   ##
=========================================
  Coverage     70.71%   70.72%           
- Complexity    10001    10004    +3     
=========================================
  Files           842      842           
  Lines         40348    40366   +18     
  Branches       6115     6116    +1     
=========================================
+ Hits          28534    28547   +13     
- Misses         9063     9069    +6     
+ Partials       2751     2750    -1     

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