chore(deps): raise tmp override to >=0.2.6 to clear high audit findings

npm audit --audit-level=high failed on four high-severity transitive
deps of @lhci/cli, all tracing to tmp <0.2.6 (tmp → external-editor →
inquirer). The existing override pinned tmp >=0.2.4, which still allowed
the vulnerable 0.2.4/0.2.5. Bumping the override to >=0.2.6 resolves
tmp to 0.2.7 and clears all high findings.

npm's own fix path (audit fix --force) would downgrade @lhci/cli to
0.1.0, a SemVer-major regression — the override avoids that.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: raifdmueller

website/package-lock.json

@@ -44,6 +44,6 @@
   "overrides": {
     "minimatch": ">=10.2.1",
     "cookie": ">=0.7.0",
-    "tmp": ">=0.2.4"
+    "tmp": ">=0.2.6"
   }
 }