Reduced logging level for collector shutdown due to context cancel

[cpheps]

Description: <Describe what has changed.
Resolves #5242

Reduced the logging level when the collector exits due to a context cancel. When the collector is exited with a canceled context it would print an error with a stack trace. This lead to confusing logs when the collector correctly shut down due to a context that was closed by signal intercepts.

Kept the context error log if the error is context.DeadlineExceeded as it's much more likely if the collector exceeded some deadline the user should be notified of such.

Link to tracking Issue: #5242

Testing: Tested locally with signal intercepts. Current unit tests are valid.

[codecov]

Codecov Report

Merging #5258 (277413c) into main (a8ad007) will decrease coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #5258      +/-   ##
==========================================
- Coverage   90.60%   90.57%   -0.04%     
==========================================
  Files         188      188              
  Lines       11092    11093       +1     
==========================================
- Hits        10050    10047       -3     
- Misses        822      825       +3     
- Partials      220      221       +1     

Impacted Files	Coverage Δ
service/collector.go	77.57% <100.00%> (+0.13%)	⬆️
pdata/internal/common.go	94.16% <0.00%> (-0.78%)	⬇️

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[cpheps]

@bogdandrutu Refactored the logging to print the error string from the context in the log so we still see the error but not the stack trace. I also removed the special deadline case.