[service] add internal factory method for meter provider

[codeboten]

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This will be used when moving the meter provider configuration to use the otel-go config package.

Part of #10414

Skipping changelog as there's no usage of this method yet. It will be done in a separate PR

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 0% with 8 lines in your changes missing coverage. Please review.

Project coverage is 92.35%. Comparing base (e014c1e) to head (db09796).

Files	Patch %	Lines
service/telemetry/internal/factory.go	0.00%	8 Missing :warning:

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #10415      +/-   ##
==========================================
- Coverage   92.39%   92.35%   -0.04%     
==========================================
  Files         393      393              
  Lines       18614    18622       +8     
==========================================
  Hits        17199    17199              
- Misses       1058     1066       +8     
  Partials      357      357              

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[github-actions[bot]]

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

[codeboten]

Ping @mx-psi for review