Bump @google-cloud/firestore from 7.11.4 to 7.11.6 in /src (#69)

Bumps [@google-cloud/firestore](https://github.com/googleapis/nodejs-firestore) from 7.11.4 to 7.11.6.
- [Release notes](https://github.com/googleapis/nodejs-firestore/releases)
- [Changelog](https://github.com/googleapis/nodejs-firestore/blob/main/CHANGELOG.md)
- [Commits](googleapis/nodejs-firestore@v7.11.4...v7.11.6)

---
updated-dependencies:
- dependency-name: "@google-cloud/firestore"
  dependency-version: 7.11.6
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

src/package-lock.json

@@ -13,7 +13,7 @@
     "test:live": "bash ../test-api.sh"
   },
   "dependencies": {
-    "@google-cloud/firestore": "7.11.4",
+    "@google-cloud/firestore": "7.11.6",
     "@google-cloud/functions-framework": "4.0.0"
   },
   "devDependencies": {