chore: Declare compatibility with Protobuf v30

PiperOrigin-RevId: 747801720

Author: vertex-sdk-bot

setup.py

@@ -298,7 +298,7 @@
         ),
         "google-auth >= 2.14.1, <3.0.0",
         "proto-plus >= 1.22.3, <2.0.0",
-        "protobuf>=3.20.2,<6.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
+        "protobuf>=3.20.2,<7.0.0,!=4.21.0,!=4.21.1,!=4.21.2,!=4.21.3,!=4.21.4,!=4.21.5",
         "packaging >= 14.3",
         "google-cloud-storage >= 1.32.0, < 3.0.0",
         "google-cloud-bigquery >= 1.15.0, < 4.0.0, !=3.20.0",

testing/constraints-3.12.txt

@@ -4,7 +4,7 @@
 google-api-core==2.21.0 # Tests google-api-core with rest async support
 google-auth==2.35.0 # Tests google-auth with rest async support
 proto-plus
-protobuf
+protobuf>=6
 mock==4.0.2
 google-cloud-storage==2.2.1 # Increased for kfp 2.0 compatibility
 packaging==24.1 # Increased to unbreak canonicalize_version error (b/377774673)