Include constraints in suggested metric names [RUN ALL RSPEC] [RUN AS-IF-FOSS]

What does this MR do?

This MR enhances automated metrics name generation feature by including variable part in metric names suggestion (enclosed in <>) if underlying metric query includes constraints (where source_table.some_col = 123) that applies to source relation of the metric. Handling joined relation is scope of follow up issue #323219 (closed)

Implementes #323193 (closed)

Test locally

Make sure that feature flag is enabled ::Feature.enable(:product_intelligence_metrics_names_suggestions)

Run generator $ bundle exec rails generate gitlab:usage_metric_definition counts.jira_imports_total_imported_issues_count --dir=7d

Screenshots (strongly suggested)

Does this MR meet the acceptance criteria?

Conformity

• 📋 Does this MR need a changelog?
  • I have included a changelog entry.
  • I have not included a changelog entry because change is behind a feature flag, and it is considered to be tooling improvement.
• [-] Documentation (if required) will be added at #323587 (closed)
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