Transition W3C Trace Context Test Service to Vanilla PHP

[yuktea]

What

Transitions the w3c-trace-context test to vanilla PHP.

Why

Speed and simplicity.

[bobstrecansky]

@yuktea - #686 has been merged. Does that unblock you on this PR?

[yuktea]

@bobstrecansky yes it does!

[codecov]

Codecov Report

Merging #695 (32a8fa6) into main (a22f9f1) will decrease coverage by 0.41%.
The diff coverage is 75.94%.

❗ Current head 32a8fa6 differs from pull request most recent head 34613ca. Consider uploading reports for the commit 34613ca to get more accurate results

@@             Coverage Diff              @@
##               main     #695      +/-   ##
============================================
- Coverage     82.78%   82.37%   -0.42%     
- Complexity     1241     1249       +8     
============================================
  Files           139      140       +1     
  Lines          3033     3052      +19     
============================================
+ Hits           2511     2514       +3     
- Misses          522      538      +16     

Flag	Coverage Δ
7.4	82.37% <76.12%> (-0.41%)	⬇️
8.0	82.43% <76.12%> (-0.41%)	⬇️
8.1	82.43% <76.12%> (-0.41%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
src/SDK/Trace/ImmutableSpan.php	100.00% <ø> (ø)
src/SDK/Trace/SpanBuilder.php	0.00% <0.00%> (ø)
src/SDK/Trace/Tracer.php	100.00% <ø> (ø)
src/SDK/Trace/TracerProvider.php	72.54% <12.50%> (-27.46%)	⬇️
src/SDK/Trace/SpanLimits.php	75.00% <77.77%> (ø)
src/SDK/Common/Attribute/AttributesBuilder.php	83.33% <83.33%> (ø)
src/SDK/Trace/Span.php	94.23% <92.00%> (+0.53%)	⬆️
src/SDK/Common/Attribute/Attributes.php	100.00% <100.00%> (ø)
src/SDK/Common/Attribute/AttributesFactory.php	100.00% <100.00%> (ø)
src/SDK/Resource/Detectors/Composer.php	85.71% <100.00%> (ø)
... and 16 more

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update a22f9f1...34613ca. Read the comment docs.

[yuktea]

Ready for review

/cc @bobstrecansky @tidal