Fix OTLP metric exporter toBuilder() loosing temporality

[JonasKunz]

Fixes #7276.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.61%. Comparing base (14e2fef) to head (2989362).
Report is 5 commits behind head on main.

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #7280      +/-   ##
============================================
- Coverage     89.62%   89.61%   -0.01%     
+ Complexity     6859     6858       -1     
============================================
  Files           780      780              
  Lines         20718    20722       +4     
  Branches       2020     2020              
============================================
+ Hits          18568    18570       +2     
- Misses         1511     1512       +1     
- Partials        639      640       +1     

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[jack-berg]

Just a couple minor comments. Thanks!