use Protobuf 33.5

Author: parthea

packages/gapic-generator/WORKSPACE

@@ -2,10 +2,10 @@ workspace(name = "gapic_generator_python")
 
 load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
 
-# Load Protobuf 35.1 first to ensure Bazel uses Protobuf 35.1 over older
+# Load Protobuf 33.5 first to ensure Bazel uses Protobuf 33.5 over older
 # transitive versions pulled in by downstream rules (e.g. gRPC or rules_gapic).
-_protobuf_version = "35.1"
-_protobuf_sha256 = "bf89df2fa0088de9c9890fbfba0076263a36c2f84847a7b54e7e32effd6201c7"
+_protobuf_version = "33.5"
+_protobuf_sha256 = "98bc55acbc30be2bda6fb8bc9169a31e14956bd3b3169c63edbe6207b8116b68"
 http_archive(
     name = "com_google_protobuf",
     sha256 = _protobuf_sha256,