[connector/exceptions] Add support for exemplars in exceptionsconnector

[marctc]

Description: <Describe what has changed.> Adds support for exemplars fort the generated metrics from exceptions. It relates the span and trace id with metrics.

The ingestion needs to be enabled via config (disbled by default).

Link to tracking Issue: Resolves #24409

Documentation: Added documentation for enabling generation of exemplars.

[github-actions[bot]]

This PR was marked stale due to lack of activity. It will be closed in 14 days.

[github-actions[bot]]

Closed as inactive. Feel free to reopen if this PR is still being worked on.

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 80.64516% with 6 lines in your changes are missing coverage. Please review.

Project coverage is 83.11%. Comparing base (cbf003e) to head (77e9bf1). Report is 481 commits behind head on main.

Files	Patch %	Lines
connector/exceptionsconnector/connector_metrics.go	80.64%	4 Missing and 2 partials :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #31819      +/-   ##
==========================================
+ Coverage   81.88%   83.11%   +1.23%     
==========================================
  Files        1858     1977     +119     
  Lines      172718   189370   +16652     
==========================================
+ Hits       141423   157400   +15977     
- Misses      26984    27139     +155     
- Partials     4311     4831     +520     

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[jpkrohling]

The tests are failing, apparently:

    connector_metrics_test.go:201: 
        	Error Trace:	/home/runner/work/opentelemetry-collector-contrib/opentelemetry-collector-contrib/connector/exceptionsconnector/connector_metrics_test.go:201
        	            				/home/runner/work/opentelemetry-collector-contrib/opentelemetry-collector-contrib/connector/exceptionsconnector/connector_metrics_test.go:169
        	            				/home/runner/work/opentelemetry-collector-contrib/opentelemetry-collector-contrib/connector/exceptionsconnector/connector_metrics_test.go:87
        	Error:      	Not equal: 
        	            	expected: 2
        	            	actual  : 1
        	Test:       	TestConnectorConsumeTraces/Test_two_consumptions

[marctc]

@jpkrohling now is ready to merge!