op-batcher: Add metrics for pending L2 transaction data size

[trianglesphere]

Description

Same as the previous version. Has been tested on the internal devnet.

[changeset-bot]

⚠️ No Changeset found

Latest commit: bfbede0

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[codecov]

Codecov Report

Merging #5865 (bfbede0) into develop (d69cb12) will increase coverage by 10.25%.
The diff coverage is 13.33%.

Additional details and impacted files

@@             Coverage Diff              @@
##           develop    #5865       +/-   ##
============================================
+ Coverage    30.38%   40.63%   +10.25%     
============================================
  Files          457      319      -138     
  Lines        29023    26092     -2931     
  Branches       877        0      -877     
============================================
+ Hits          8818    10603     +1785     
+ Misses       19644    14513     -5131     
- Partials       561      976      +415     

Flag	Coverage Δ
bedrock-go-tests	40.63% <13.33%> (+15.23%)	⬆️
common-ts-tests	?
contracts-bedrock-tests	?
contracts-tests	?
core-utils-tests	?
dtl-tests	?
fault-detector-tests	?
sdk-tests	?

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
op-batcher/metrics/metrics.go	0.00% <0.00%> (ø)
op-batcher/batcher/channel_manager.go	82.19% <100.00%> (+0.16%)	⬆️
op-batcher/metrics/noop.go	53.33% <100.00%> (+7.17%)	⬆️

... and 265 files with indirect coverage changes

[mergify]

This PR has been added to the merge queue, and will be merged soon.

[mergify]

This PR is next in line to be merged, and will be merged as soon as checks pass.