Update dependency graphql-subscriptions to v1.2.1

Editor assessment

Updating graphql-subscriptions to v1.2.1 under fix(deps) names the dependency and the target version exactly. The fix type follows the project's renovate convention for runtime dependency refreshes — a valid house choice rather than a defect. The subject fully identifies the change without requiring the diff. No body follows, and none is owed for a version bump; no footers appear. Hygiene is clean: imperative mood, no trailing period, precise subject, no ticket junk, no pasted material. A routine dependency refresh communicated cleanly in one line.