chore: test protobuf 4.31 [no need to review]

ldetmer · web-flow · commit beb917a430f8 · 2025-05-20T15:28:21.000-04:00
diff --git a/.kokoro/build.sh b/.kokoro/build.sh
@@ -70,6 +70,7 @@ integration)
       -Dcheckstyle.skip=true \
       -DskipUnitTests=true \
       -Dfmt.skip=true \
+      -Dprotobuf.version=4.31.0-RC1 \
       -fae \
       verify
     RETURN_CODE=$?
