chore: remove workspace py_proto_library example (#3546)

Also update the deleted package file

Author: rickeylev

.bazelci/presubmit.yml

@@ -421,33 +421,6 @@ tasks:
   # We don't run pip_parse_vendored under Windows as the file checked in is
   # generated from a repository rule containing OS-specific rendered paths.
 
-  # The proto example is workspace-only; bzlmod functionality is covered
-  # by examples/bzlmod/py_proto_library
-  integration_test_py_proto_library_ubuntu_workspace:
-    <<: *reusable_build_test_all
-    <<: *common_workspace_flags
-    name: "examples/py_proto_library: Ubuntu, workspace"
-    working_directory: examples/py_proto_library
-    platform: ubuntu2204
-  integration_test_py_proto_library_debian_workspace:
-    <<: *reusable_build_test_all
-    <<: *common_workspace_flags
-    name: "examples/py_proto_library: Debian, workspace"
-    working_directory: examples/py_proto_library
-    platform: debian11
-  integration_test_py_proto_library_macos_workspace:
-    <<: *reusable_build_test_all
-    <<: *common_workspace_flags
-    name: "examples/py_proto_library: MacOS, workspace"
-    working_directory: examples/py_proto_library
-    platform: macos_arm64
-  integration_test_py_proto_library_windows_workspace:
-    <<: *reusable_build_test_all
-    <<: *common_workspace_flags
-    name: "examples/py_proto_library: Windows, workspace"
-    working_directory: examples/py_proto_library
-    platform: windows
-
   integration_test_pip_repository_annotations_ubuntu_workspace:
     <<: *reusable_build_test_all
     <<: *common_workspace_flags

.bazelrc.deleted_packages

@@ -8,10 +8,6 @@ common --deleted_packages=examples/bzlmod/libs/my_lib
 common --deleted_packages=examples/bzlmod/other_module
 common --deleted_packages=examples/bzlmod/other_module/other_module/pkg
 common --deleted_packages=examples/bzlmod/patches
-common --deleted_packages=examples/bzlmod/py_proto_library
-common --deleted_packages=examples/bzlmod/py_proto_library/example.com/another_proto
-common --deleted_packages=examples/bzlmod/py_proto_library/example.com/proto
-common --deleted_packages=examples/bzlmod/py_proto_library/foo_external
 common --deleted_packages=examples/bzlmod/runfiles
 common --deleted_packages=examples/bzlmod/tests
 common --deleted_packages=examples/bzlmod/tests/other_module
@@ -22,9 +18,6 @@ common --deleted_packages=examples/multi_python_versions/tests
 common --deleted_packages=examples/pip_parse
 common --deleted_packages=examples/pip_parse_vendored
 common --deleted_packages=examples/pip_repository_annotations
-common --deleted_packages=examples/py_proto_library
-common --deleted_packages=examples/py_proto_library/example.com/another_proto
-common --deleted_packages=examples/py_proto_library/example.com/proto
 common --deleted_packages=gazelle
 common --deleted_packages=gazelle/examples/bzlmod_build_file_generation
 common --deleted_packages=gazelle/examples/bzlmod_build_file_generation/other_module/other_module/pkg