chore(deps): update dependency protobuf to v6

Author: renovate-bot

requirements.txt

@@ -344,18 +344,16 @@ proto-plus==1.26.1 \
     # via
     #   google-api-core
     #   google-cloud-spanner
-protobuf==5.29.3 \
-    --hash=sha256:0a18ed4a24198528f2333802eb075e59dea9d679ab7a6c5efb017a59004d849f \
-    --hash=sha256:0eb32bfa5219fc8d4111803e9a690658aa2e6366384fd0851064b963b6d1f2a7 \
-    --hash=sha256:3ea51771449e1035f26069c4c7fd51fba990d07bc55ba80701c78f886bf9c888 \
-    --hash=sha256:5da0f41edaf117bde316404bad1a486cb4ededf8e4a54891296f648e8e076620 \
-    --hash=sha256:6ce8cc3389a20693bfde6c6562e03474c40851b44975c9b2bf6df7d8c4f864da \
-    --hash=sha256:84a57163a0ccef3f96e4b6a20516cedcf5bb3a95a657131c5c3ac62200d23252 \
-    --hash=sha256:a4fa6f80816a9a0678429e84973f2f98cbc218cca434abe8db2ad0bffc98503a \
-    --hash=sha256:a8434404bbf139aa9e1300dbf989667a83d42ddda9153d8ab76e0d5dcaca484e \
-    --hash=sha256:b89c115d877892a512f79a8114564fb435943b59067615894c3b13cd3e1fa107 \
-    --hash=sha256:c027e08a08be10b67c06bf2370b99c811c466398c357e615ca88c91c07f0910f \
-    --hash=sha256:daaf63f70f25e8689c072cfad4334ca0ac1d1e05a92fc15c54eb9cf23c3efd84
+protobuf==6.30.1 \
+    --hash=sha256:3c25e51e1359f1f5fa3b298faa6016e650d148f214db2e47671131b9063c53be \
+    --hash=sha256:47cd320b7db63e8c9ac35f5596ea1c1e61491d8a8eb6d8b45edc44760b53a4f6 \
+    --hash=sha256:535fb4e44d0236893d5cf1263a0f706f1160b689a7ab962e9da8a9ce4050b780 \
+    --hash=sha256:554d7e61cce2aa4c63ca27328f757a9f3867bce8ec213bf09096a8d16bcdcb6a \
+    --hash=sha256:aa4f7dfaed0d840b03d08d14bfdb41348feaee06a828a8c455698234135b4075 \
+    --hash=sha256:b510f55ce60f84dc7febc619b47215b900466e3555ab8cb1ba42deb4496d6cc0 \
+    --hash=sha256:ba0706f948d0195f5cac504da156d88174e03218d9364ab40d903788c1903d7e \
+    --hash=sha256:e3083660225fa94748ac2e407f09a899e6a28bf9c0e70c75def8d15706bf85fc \
+    --hash=sha256:ed484f9ddd47f0f1bf0648806cccdb4fe2fb6b19820f9b79a5adf5dcfd1b8c5f
     # via
     #   google-api-core
     #   google-cloud-spanner