chore(deps): update dependency @google-cloud/datastore to v7 (#1449)

Author: renovate-bot

package.json

@@ -49,7 +49,7 @@
   },
   "devDependencies": {
     "@compodoc/compodoc": "1.1.18",
-    "@google-cloud/datastore": "^6.0.0",
+    "@google-cloud/datastore": "^7.0.0",
     "@grpc/proto-loader": "^0.6.0",
     "@types/builtin-modules": "^2.0.0",
     "@types/console-log-level": "^1.4.0",