chore(deps): update dependency protobuf to v6

Author: renovate-bot

requirements.txt

@@ -340,18 +340,16 @@ proto-plus==1.26.1 \
     # via
     #   google-api-core
     #   google-cloud-spanner
-protobuf==5.29.4 \
-    --hash=sha256:13eb236f8eb9ec34e63fc8b1d6efd2777d062fa6aaa68268fb67cf77f6839ad7 \
-    --hash=sha256:1832f0515b62d12d8e6ffc078d7e9eb06969aa6dc13c13e1036e39d73bebc2de \
-    --hash=sha256:307ecba1d852ec237e9ba668e087326a67564ef83e45a0189a772ede9e854dd0 \
-    --hash=sha256:3fde11b505e1597f71b875ef2fc52062b6a9740e5f7c8997ce878b6009145862 \
-    --hash=sha256:476cb7b14914c780605a8cf62e38c2a85f8caff2e28a6a0bad827ec7d6c85d68 \
-    --hash=sha256:4f1dfcd7997b31ef8f53ec82781ff434a28bf71d9102ddde14d076adcfc78c99 \
-    --hash=sha256:678974e1e3a9b975b8bc2447fca458db5f93a2fb6b0c8db46b6675b5b5346812 \
-    --hash=sha256:aec4962f9ea93c431d5714ed1be1c93f13e1a8618e70035ba2b0564d9e633f2e \
-    --hash=sha256:bcefcdf3976233f8a502d265eb65ea740c989bacc6c30a58290ed0e519eb4b8d \
-    --hash=sha256:d7d3f7d1d5a66ed4942d4fefb12ac4b14a29028b209d4bfb25c68ae172059922 \
-    --hash=sha256:fd32223020cb25a2cc100366f1dedc904e2d71d9322403224cdde5fdced0dabe
+protobuf==6.31.0 \
+    --hash=sha256:00a873c06efdfb854145d9ded730b09cf57d206075c38132674093370e2edabb \
+    --hash=sha256:10bd62802dfa0588649740a59354090eaf54b8322f772fbdcca19bc78d27f0d6 \
+    --hash=sha256:2c812f0f96ceb6b514448cefeb1df54ec06dde456783f5099c0e2f8a0f2caa89 \
+    --hash=sha256:314fab1a6a316469dc2dd46f993cbbe95c861ea6807da910becfe7475bc26ffe \
+    --hash=sha256:3e987c99fd634be8347246a02123250f394ba20573c953de133dc8b2c107dd71 \
+    --hash=sha256:5353e38844168a327acd2b2aa440044411cd8d1b6774d5701008bd1dba067c79 \
+    --hash=sha256:67ce50195e4e584275623b8e6bc6d3d3dfd93924bf6116b86b3b8975ab9e4571 \
+    --hash=sha256:6ac2e82556e822c17a8d23aa1190bbc1d06efb9c261981da95c71c9da09e9e23 \
+    --hash=sha256:96d8da25c83b11db5fe9e0376351ce25e7205e13224d939e097b6f82a72af824
     # via
     #   google-api-core
     #   google-cloud-spanner