Remove some unused code from tracing module

[0xnm]

What does this PR do?

This PR removes some unused/impossible code from the tracing module:

• Accessing arbitrary file paths: it is not possible to access them on Android
• Remove code depending on mac, native image, windows checks
• Remove JFR (Java Flight Recorder) checks
• Remove data streams blocks

This PR doesn't do a complete cleanup, just tries to address the simplest things.

Review checklist (to be filled by reviewers)

• Feature or bugfix MUST have appropriate tests (unit, integration, e2e)
• Make sure you discussed the feature or bugfix with the maintaining team in an Issue
• Make sure each commit and the PR mention the Issue number (cf the CONTRIBUTING doc)

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 80.00000% with 2 lines in your changes missing coverage. Please review.

Project coverage is 68.59%. Comparing base (f2af2ad) to head (be68d62).

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #2079      +/-   ##
===========================================
+ Coverage    67.46%   68.59%   +1.13%     
===========================================
  Files          735      719      -16     
  Lines        27002    26560     -442     
  Branches      4562     4468      -94     
===========================================
+ Hits         18215    18218       +3     
+ Misses        7569     7141     -428     
+ Partials      1218     1201      -17     

Files	Coverage Δ
...og/opentracing/decorators/DDDecoratorsFactory.java	50.00% <ø> (ø)
...ain/java/com/datadog/trace/api/ConfigDefaults.java	100.00% <ø> (ø)
...java/com/datadog/trace/api/InstrumenterConfig.java	55.67% <100.00%> (+3.29%)	⬆️
.../src/main/java/com/datadog/trace/api/Platform.java	45.45% <ø> (+0.50%)	⬆️
...ace/bootstrap/instrumentation/api/AgentTracer.java	8.11% <ø> (+0.46%)	⬆️
...adog/trace/common/writer/TraceStructureWriter.java	47.83% <ø> (+3.38%)	⬆️
...c/main/java/com/datadog/trace/core/CoreTracer.java	71.53% <100.00%> (-0.14%)	⬇️
...ava/com/datadog/trace/util/AgentThreadFactory.java	82.05% <100.00%> (-2.73%)	⬇️
.../src/main/java/com/datadog/trace/util/Strings.java	6.90% <ø> (+4.18%)	⬆️
...ce/src/main/java/com/datadog/trace/api/Config.java	63.58% <50.00%> (+4.58%)	⬆️

... and 32 files with indirect coverage changes

[mariusc83]

LGTM