Make AttributesInterface immutable

[Nevay]

Makes AttributesInterface immutable by introducing AttributesBuilderInterface as mutable builder.

Resolves #709, see also #542.

[codecov]

Codecov Report

Merging #724 (572712e) into main (122aff0) will decrease coverage by 0.04%.
The diff coverage is 83.09%.

@@             Coverage Diff              @@
##               main     #724      +/-   ##
============================================
- Coverage     82.41%   82.37%   -0.05%     
- Complexity     1247     1249       +2     
============================================
  Files           139      140       +1     
  Lines          3048     3052       +4     
============================================
+ Hits           2512     2514       +2     
- Misses          536      538       +2     

Flag	Coverage Δ
7.4	82.37% <83.45%> (-0.03%)	⬇️
8.0	82.43% <83.45%> (-0.03%)	⬇️
8.1	82.43% <83.45%> (-0.03%)	⬇️

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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/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)
src/SDK/Resource/Detectors/Environment.php	100.00% <100.00%> (ø)
... and 15 more

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