chore: upgrade to gapic-generator-python v0.29.0

Also enables the 'add-iam-method' option for KMS and Pub/Sub.

https://github.com/googleapis/gapic-generator-python/releases/tag/v0.29.0

PiperOrigin-RevId: 322659285

WORKSPACE

@@ -223,8 +223,8 @@ pip_repositories()
 # Change upstream repository once PR is merged
 http_archive(
     name = "gapic_generator_python",
-    urls = ["https://github.com/googleapis/gapic-generator-python/archive/v0.28.1.zip"],
-    strip_prefix = "gapic-generator-python-0.28.1",
+    urls = ["https://github.com/googleapis/gapic-generator-python/archive/v0.29.0.zip"],
+    strip_prefix = "gapic-generator-python-0.29.0",
 )
 
 load("@gapic_generator_python//:repositories.bzl",

google/cloud/kms/v1/BUILD.bazel

@@ -164,64 +164,27 @@ go_gapic_assembly_pkg(
 ##############################################################################
 # Python
 ##############################################################################
+# This library is using Python microgenerator.
+# DO NOT OVERRIDE this Python section with autogenerated rules.
 load(
     "@com_google_googleapis_imports//:imports.bzl",
-    "moved_proto_library",
-    "py_gapic_assembly_pkg",
-    "py_gapic_library",
-    "py_grpc_library",
-    "py_proto_library",
-)
-
-moved_proto_library(
-    name = "kms_moved_proto",
-    srcs = [":kms_proto"],
-    deps = [
-        "//google/api:annotations_proto",
-        "//google/api:client_proto",
-        "//google/api:field_behavior_proto",
-        "//google/api:resource_proto",
-        "@com_google_protobuf//:duration_proto",
-        "@com_google_protobuf//:field_mask_proto",
-        "@com_google_protobuf//:timestamp_proto",
-    ],
-)
-
-py_proto_library(
-    name = "kms_py_proto",
-    plugin = "@protoc_docs_plugin//:docs_plugin",
-    deps = [":kms_moved_proto"],
-)
-
-py_grpc_library(
-    name = "kms_py_grpc",
-    srcs = [":kms_moved_proto"],
-    deps = [":kms_py_proto"],
+    py_gapic_assembly_pkg = "py_gapic_assembly_pkg2",
+    py_gapic_library = "py_gapic_library2",
 )
 
 py_gapic_library(
     name = "kms_py_gapic",
-    src = ":kms_proto_with_info",
-    gapic_yaml = "cloudkms_gapic.yaml",
+    srcs = [":kms_proto"],
     grpc_service_config = "cloudkms_grpc_service_config.json",
-    package = "google.cloud.kms.v1",
-    service_yaml = "cloudkms_v1.yaml",
-    deps = [
-        ":kms_py_grpc",
-        ":kms_py_proto",
-    ],
+    opt_args = ["add-iam-methods"]
 )
 
-# Open Source Packages
 py_gapic_assembly_pkg(
     name = "kms-v1-py",
     deps = [
         ":kms_py_gapic",
-        ":kms_py_grpc",
-        ":kms_py_proto",
     ],
 )
-
 ##############################################################################
 # PHP
 ##############################################################################

google/pubsub/v1/BUILD.bazel

@@ -119,6 +119,7 @@ py_gapic_library(
     name = "pubsub_py_gapic",
     srcs = [":pubsub_proto"],
     grpc_service_config = "pubsub_grpc_service_config.json",
+    opt_args = ["add-iam-methods"]
 )
 
 py_gapic_assembly_pkg(