fix: don't fail release jobs when gh CLI is missing on the runner

[odinr]

Why is this change needed?
The fusion-gh-runner-fusion-framework self-hosted runner doesn't have the GitHub CLI (gh) installed. This broke the "convert Changeset PR to draft" step in ci.yml's release-pkg job on the last run (gh: command not found, exit 127): https://github.com/equinor/fusion-framework/actions/runs/32279766760/job/96155504260. The same step exists in next.yml's release-pkg job on the same runner label.

What is the current behavior?
Both steps hard-fail the whole job when a changeset PR needs converting to draft, blocking the release/pre-release workflow entirely.

What is the new behavior?
Both steps are now continue-on-error: true. Worst case, the changeset PR just stays open/ready instead of being converted to draft — non-blocking.

What is the intended behavior or invariant?
This is a stopgap. Infra has been notified separately to install gh on the fusion-gh-runner-fusion-framework runner image; once that's done, these steps will succeed again as before and continue-on-error becomes a no-op safety net rather than the primary fix.

Does this PR introduce a breaking change?
No.

Impact assessment:

• Breaking changes: No
• Version bump: N/A (workflow-only change, no changeset needed)
• Consumer impact: None
• Downstream impact: None

Review guidance:
Confirmed via job log that gh is genuinely absent on this runner (not a transient issue), and that these are the only two gh-CLI-consuming steps running on fusion-gh-runner-fusion-framework in the whole workflow set (other jobs on that runner don't call gh; other workflows that do call gh run on ubuntu-latest, which ships it).

Additional context
None.

Related issues
None.

Checklist

• Confirm completion of the self-review checklist
• Confirm TSDoc captures intent for functions, hooks, components, classes, and named arrow functions
• Confirm iterator blocks, decision gates, RxJS chains, and complex decisions explain why they exist
• Confirm React logic and derived values are resolved before markup when applicable
• Confirm README/docs are updated for user-facing changes
• Confirm changes to target branch validation
  • Included files validated
  • No new linting warnings
  • Not a duplicate PR
• Confirm adherence to code of conduct

[changeset-bot]

⚠️ No Changeset found

Latest commit: 5da73b4

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