chore: update default ignores for Python libraries (#586)

Author: busunkim96

synthtool/gcp/templates/python_library/.flake8

@@ -21,6 +21,8 @@ exclude =
   # Exclude generated code.
   **/proto/**
   **/gapic/**
+  **/services/**
+  **/types/**
   *_pb2.py
 
   # Standard linting exemptions.

synthtool/gcp/templates/python_library/.gitignore

@@ -10,6 +10,7 @@
 dist
 build
 eggs
+.eggs
 parts
 bin
 var
@@ -49,6 +50,7 @@ bigquery/docs/generated
 # Virtual environment
 env/
 coverage.xml
+sponge_log.xml
 
 # System test environment variables.
 system_tests/local_test_setup

synthtool/gcp/templates/python_library/MANIFEST.in

@@ -20,3 +20,6 @@ recursive-include google *.json *.proto
 recursive-include tests *
 global-exclude *.py[co]
 global-exclude __pycache__
+
+# Exclude scripts for samples readmegen
+prune scripts/readme-gen