chore: update gax dependency (#1719)

Author: sofisl

tools/package.json

@@ -30,7 +30,7 @@
   "dependencies": {
     "@babel/core": "^7.26.8",
     "@babel/traverse": "^7.26.8",
-    "google-gax": "^4.4.1",
+    "google-gax": "^5.0.0-rc.0",
     "google-proto-files": "^4.2.0",
     "protobufjs-cli": "^1.1.3",
     "uglify-js": "^3.19.3",