chore(deps): update dependency protobuf to v6

Author: renovate-bot

.kokoro/requirements.txt

@@ -380,18 +380,16 @@ platformdirs==3.11.0 \
     --hash=sha256:cf8ee52a3afdb965072dcc652433e0c7e3e40cf5ea1477cd4b3b1d2eb75495b3 \
     --hash=sha256:e9d171d00af68be50e9202731309c4e658fd8bc76f55c11c7dd760d023bda68e
     # via virtualenv
-protobuf==4.25.6 \
-    --hash=sha256:07972021c8e30b870cfc0863409d033af940213e0e7f64e27fe017b929d2c9f7 \
-    --hash=sha256:3f3b0b39db04b509859361ac9bca65a265fe9342e6b9406eda58029f5b1d10b2 \
-    --hash=sha256:4434ff8bb5576f9e0c78f47c41cdf3a152c0b44de475784cd3fd170aef16205a \
-    --hash=sha256:5dd800da412ba7f6f26d2c08868a5023ce624e1fdb28bccca2dc957191e81fb5 \
-    --hash=sha256:61df6b5786e2b49fc0055f636c1e8f0aff263808bb724b95b164685ac1bcc13a \
-    --hash=sha256:6d4381f2417606d7e01750e2729fe6fbcda3f9883aa0c32b51d23012bded6c91 \
-    --hash=sha256:6ef2045f89d4ad8d95fd43cd84621487832a61d15b49500e4c1350e8a0ef96be \
-    --hash=sha256:8bad0f9e8f83c1fbfcc34e573352b17dfce7d0519512df8519994168dc015d7d \
-    --hash=sha256:b6905b68cde3b8243a198268bb46fbec42b3455c88b6b02fb2529d2c306d18fc \
-    --hash=sha256:b8f837bfb77513fe0e2f263250f423217a173b6d85135be4d81e96a4653bcd3c \
-    --hash=sha256:f8cfbae7c5afd0d0eaccbe73267339bff605a2315860bb1ba08eb66670a9a91f
+protobuf==6.30.0 \
+    --hash=sha256:501810e0eba1d327e783fde47cc767a563b0f1c292f1a3546d4f2b8c3612d4d0 \
+    --hash=sha256:52d4bb6fe76005860e1d0b8bfa126f5c97c19cc82704961f60718f50be16942d \
+    --hash=sha256:7337d76d8efe65ee09ee566b47b5914c517190196f414e5418fa236dfd1aed3e \
+    --hash=sha256:7940ab4dfd60d514b2e1d3161549ea7aed5be37d53bafde16001ac470a3e202b \
+    --hash=sha256:852b675d276a7d028f660da075af1841c768618f76b90af771a8e2c29e6f5965 \
+    --hash=sha256:9b33d51cc95a7ec4f407004c8b744330b6911a37a782e2629c67e1e8ac41318f \
+    --hash=sha256:bb35ad251d222f03d6c4652c072dfee156be0ef9578373929c1a7ead2bd5492c \
+    --hash=sha256:d79bf6a202a536b192b7e8d295d7eece0c86fbd9b583d147faf8cfeff46bf598 \
+    --hash=sha256:e5ef216ea061b262b8994cb6b7d6637a4fb27b3fb4d8e216a6040c0b93bd10d7
     # via
     #   gcp-docuploader
     #   gcp-releasetool