tools/jdk: disable implicit __init__.py creation for proguard_allowlister

[dhalperi]

Set legacy_create_init = 0 on the proguard_allowlister py_binary and
py_test to silence the deprecation warning about implicit __init__.py
creation. These targets do not rely on implicitly created __init__.py
files.

See bazel-contrib/rules_python#2945

======================================================================
WARNING: Target @@bazel_tools//tools/jdk:proguard_allowlister is using implicit __init__.py creation.
  This diabolic behavior is deprecated and will be disabled by default in a
  future release.
  See https://github.com/bazel-contrib/rules_python/issues/2945

  Ensure all __init__.py files are explicitly created and
  added to the srcs or deps of your targets.

  Disable implicit creation by setting:
    legacy_create_init = 0
  on the target, or globally by setting:
    --incompatible_default_to_explicit_init_py
======================================================================