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==6.30.2 \
+    --hash=sha256:0eb523c550a66a09a0c20f86dd554afbf4d32b02af34ae53d93268c1f73bc65b \
+    --hash=sha256:35c859ae076d8c56054c25b59e5e59638d86545ed6e2b6efac6be0b6ea3ba048 \
+    --hash=sha256:4f6c687ae8efae6cf6093389a596548214467778146b7245e886f35e1485315d \
+    --hash=sha256:50f32cc9fd9cb09c783ebc275611b4f19dfdfb68d1ee55d2f0c7fa040df96815 \
+    --hash=sha256:524afedc03b31b15586ca7f64d877a98b184f007180ce25183d1a5cb230ee72b \
+    --hash=sha256:7653c99774f73fe6b9301b87da52af0e69783a2e371e8b599b3e9cb4da4b12b9 \
+    --hash=sha256:acec579c39c88bd8fbbacab1b8052c793efe83a0a5bd99db4a31423a25c0a0e2 \
+    --hash=sha256:ae86b030e69a98e08c77beab574cbcb9fff6d031d57209f574a5aea1445f4b51 \
+    --hash=sha256:b12ef7df7b9329886e66404bef5e9ce6a26b54069d7f7436a0853ccdeb91c103
     # via
     #   google-api-core
     #   google-cloud-spanner