chore(deps): update dependency @grpc/proto-loader to ^0.6.0 (#1339)

Author: renovate-bot

package.json

@@ -52,7 +52,7 @@
   "devDependencies": {
     "@compodoc/compodoc": "1.1.11",
     "@google-cloud/datastore": "^6.0.0",
-    "@grpc/proto-loader": "^0.5.0",
+    "@grpc/proto-loader": "^0.6.0",
     "@types/builtin-modules": "^2.0.0",
     "@types/console-log-level": "^1.4.0",
     "@types/continuation-local-storage": "^3.2.1",