Fix rest metrics instantiation - auto update to onflow/cadence v0.40.0

[peterargue]

Description

Fixes issues with rest metrics initialization discovered by #461

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For contributor use:

• Targeted PR against master branch
• Linked to GitHub issue with discussion and accepted design OR link to spec that describes this work
• Code follows the standards mentioned here
• Updated relevant documentation
• Re-reviewed Files changed in the GitHub PR explorer
• Added appropriate labels

[codecov-commenter]

Codecov Report

❗ No coverage uploaded for pull request base (auto-update-onflow-cadence-v0.40.0@02a44bf). Click here to learn what that means.
The diff coverage is n/a.

@@                          Coverage Diff                          @@
##             auto-update-onflow-cadence-v0.40.0     #462   +/-   ##
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  Coverage                                      ?   54.85%           
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  Files                                         ?       28           
  Lines                                         ?     3617           
  Branches                                      ?        0           
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  Hits                                          ?     1984           
  Misses                                        ?     1473           
  Partials                                      ?      160           

Flag	Coverage Δ
unittests	54.85% <0.00%> (?)

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[turbolent]

Great! Thank you 🙏