Remove explicit Gitlab::Metrics.action assignments, are already automatic.

Merged Paco Guzman requested to merge 18760-remove-explicate-assignment-on-metrics-action into master

What does this MR do?

Remove explicit call not needed anymore

Are there points in the code the reviewer needs to double check?


Why was this MR needed?

Remove technical debt

What are the relevant issue numbers?

Closes #18760 (closed)