dependencies: rollback to v29.0 Java gRPC compiler

Author: raphael-goetz

buf.gen.yaml

@@ -2,7 +2,7 @@ version: v2
 
 plugins:
 
-  - remote: buf.build/protocolbuffers/java
+  - remote: buf.build/protocolbuffers/java:v29.0
     out: sdk/java/src/main/java
 
   - remote: buf.build/grpc/java