Remove srcs_version and python_version attributes, as they already default to "PY3"

PiperOrigin-RevId: 721269125

Author: tfx-copybara

tensorflow_data_validation/tools/BUILD

@@ -9,8 +9,6 @@ package(default_visibility = ["//tensorflow_data_validation:__subpackages__"])
 py_binary(
  name = "build_docs",
  srcs = ["build_docs.py"],
- python_version = "PY3",
- srcs_version = "PY3",
  deps = [
  "# Implicit absl dependency:app",
  "# Implicit apache_beam dependency.",