config: NewSDK can return valid MeterProvider

[codeboten]

Follow up to #4741, does the same but for metric signal.

Fixes #4371

~Will rebase once 4741 is merged~

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 84.72222% with 22 lines in your changes are missing coverage. Please review.

Project coverage is 62.1%. Comparing base (7a9e861) to head (997c85e).

Additional details and impacted files

@@           Coverage Diff           @@
##            main   #4804     +/-   ##
=======================================
+ Coverage   61.8%   62.1%   +0.2%     
=======================================
  Files        186     186             
  Lines      11388   11527    +139     
=======================================
+ Hits        7049    7166    +117     
- Misses      4137    4149     +12     
- Partials     202     212     +10     

Files	Coverage Δ
config/config.go	85.0% <33.3%> (-4.5%)	:arrow_down:
config/metric.go	85.9% <85.8%> (-14.1%)	:arrow_down:

[pellared]

@codeboten Can you please update the branch (resolve conflicts)? I will do my best to review the PR this week.

[linux-foundation-easycla[bot]]

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• :white_check_mark: login: codeboten / name: Alex Boten (997c85e3f781f79c793536a7aece4b1baef5a024)