Document and remove unused code

Declare components in a consistent way;
Use " instead of ' to improve consistency;
Update documentation;
Fix commit author verification to match the use cases;

Adds tests for the added components

Fix paths in pagination spec

Adds tests to pipelines table used in merge requests and commits

Use same resource interceptor

Fix eslint error

Create shared folder for vue common files
Update paths

Second iteration - refactor main component to be 100% reusable between the 3 tables

expand remaining non-explicit eslint-disable blocks and factor out globals when no-undef encountered

decrement outstanding resource counts when HTTP response is received

Before the count would be reduced 500 ms after a DOM update tick, which could
cause race conditions since the `DatabaseCleaner` could run in the middle of
a Rails controller handling the response.

Partial fix to #21197 and other intermittent spec failures.