Change SUS labels to scoped labels in triage-ops

Context

Relates to #982 (closed)

We have recently renamed ~SUS and ~"non-SUS" labels to ~SUS::Impacting and ~SUS::Non-impacting respectively.

What does this MR do?

We adapt the codebase to only work with the new scoped SUS labels (i.e. ~SUS::Impacting and ~SUS::Non-impacting)

The MR is in draft because it should not be merged right now.

Verify this MR with dry-runs

Dry-run for policies/stages/hygiene/ask-severity-for-sus-impacting-issues.yml

Ask for severity label on SUS-impacting issues

• Dry-run: Issues 1,4, and 7
• Real data: Issues 1,4, and 7
• Rationale: Those issues have a ~SUS::* label without a severity label associated. The older SUS labels are not affected anymore.

Remove automation:ux-missing-labels from issues with severity

No changes made there.

Dry-run for policies/stages/hygiene/label-sus-issues.yml

Add ~SUS::Impacting to open issues with qualifying SUS-impacting label

• Dry-run: Issues 3 and 10
• Real data: Issues 3 and 10

Add ~SUS::Impacting to open issues with UX + typebug

• Dry-run: Issues 5 and 11
• Real data: Issues 5 and 11

Replace ~SUS::Impacting with ~SUS::Non-impacting if ~feature::addition or ~Actionable Insight::exploration needed labels are present

• Dry-run: Issue 7
• Real data: Issue 7

Migration

Migration path

• Coordinate with @jmandell to tell them that we are ready
• Rename the old ~SUS flags to the new ~SUS::* flags
• Merge/deploy this MR

After the migration

• Remove the ~SUS::* labels inside the https://gitlab.com/gitlab-org/quality/engineering-productivity/triage-ops-playground project