chore: Migrate python-pubsub synth.py from artman to bazel (#80)

synth.py

@@ -14,23 +14,20 @@
 
 """This script is used to synthesize generated parts of this library."""
 
-import re
-import textwrap
-
 import synthtool as s
 from synthtool import gcp
 
-gapic = gcp.GAPICGenerator()
+gapic = gcp.GAPICBazel()
 common = gcp.CommonTemplates()
 version = "v1"
 
 # ----------------------------------------------------------------------------
 # Generate pubsub GAPIC layer
 # ----------------------------------------------------------------------------
 library = gapic.py_library(
-    "pubsub",
-    version,
-    config_path="/google/pubsub/artman_pubsub.yaml",
+    service="pubsub",
+    version=version,
+    bazel_target="//google/pubsub/v1:pubsub-v1-py",
     include_protos=True,
 )
 s.move(