Fixed an issue where otellogr emits nil context which leads to panic in exporters

[flc1125]

Fixed #6509

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 68.5%. Comparing base (00786cc) to head (896c809).

Additional details and impacted files

@@          Coverage Diff          @@
##            main   #6527   +/-   ##
=====================================
  Coverage   68.5%   68.5%           
=====================================
  Files        200     200           
  Lines      16768   16784   +16     
=====================================
+ Hits       11490   11506   +16     
  Misses      4933    4933           
  Partials     345     345           

Files with missing lines	Coverage Δ
bridges/otellogr/logsink.go	100.0% <100.0%> (ø)