fix(ci): disable telemetry in release workflow to fix test failures (#1442)

The release workflow's "Update snapshots" step fails because
withCommandRunTelemetry triggers real filesystem and network I/O
(createClient → getOrCreateInstallationId → mkdir/writeFile, plus
OtelMetricSink construction and flush) that doesn't resolve within
the 50-100ms test delays.

build-and-test.yml already sets AGENTCORE_TELEMETRY_DISABLED=1 at the
workflow level, preventing this. The release workflow was missing it.

Co-authored-by: jariy17 <tjariy+jariy17@users.noreply.github.com>

Author: jariy17

.github/workflows/release-main-and-preview.yml

@@ -45,6 +45,9 @@ permissions:
   contents: write
   pull-requests: write
 
+env:
+  AGENTCORE_TELEMETRY_DISABLED: '1'
+
 jobs:
   # ═══════════════════════════════════════════════════════════════════
   # Step 1 — Prepare release (bump both versions, single PR)