feat(label_new_contributor): link to the 'why is my PR not on the queue' dashboard

[grunweg]

Follow-up to #35109, discussed also on zulip.

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The link put into the comment pre-fills a search for the PR number: Chris Henson has tested that the interpolation works correctly.

[github-actions]

PR summary 332fc33e62

Import changes for modified files

No significant changes to the import graph

Import changes for all files

Files	Import difference

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Declarations diff

No declarations were harmed in the making of this PR! 🐙

You can run this locally as follows

## summary with just the declaration names:
./scripts/declarations_diff.sh <optional_commit>

## more verbose report:
./scripts/declarations_diff.sh long <optional_commit>

The doc-module for scripts/declarations_diff.sh contains some details about this script.

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No changes to technical debt.

You can run this locally as

./scripts/technical-debt-metrics.sh pr_summary

• The relative value is the weighted sum of the differences with weight given by the inverse of the current value of the statistic.
• The absolute value is the relative value divided by the total sum of the inverses of the current values (i.e. the weighted average of the differences).

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Workflow documentation reminder

This PR modifies files under .github/workflows/.
Please update docs/workflows.md if the workflow inventory, triggers, or behavior changed.

Modified workflow files:

• .github/workflows/label_new_contributor.yml