Add missing _optionally_create_directory in Android user_log_dir and user_runtime_dir

[bysiber]

Summary

When ensure_exists=True is set, the Unix implementation correctly calls _optionally_create_directory on the opinionated subdirectory for user_log_dir (the log subdir). However, the Android implementation is missing these calls for both user_log_dir and user_runtime_dir.

Problem

On Android, calling user_log_dir or user_runtime_dir with ensure_exists=True and opinion=True does not create the opinionated subdirectories (log and tmp respectively), even though the parent cache directory is created. This is inconsistent with the Unix implementation which does call _optionally_create_directory after appending the log subdirectory.

For example, comparing user_log_dir in both platforms:

Unix (correct):

if self.opinion:
    path = os.path.join(path, "log")
    self._optionally_create_directory(path)

Android (before this fix):

if self.opinion:
    path = os.path.join(path, "log")
# missing _optionally_create_directory call

Fix

Added self._optionally_create_directory(path) calls in user_log_dir and user_runtime_dir within the if self.opinion: blocks, matching the existing Unix behavior.

[gaborbernat]

Test?

[bysiber]

Added a parametrized test that verifies user_log_dir and user_runtime_dir actually create the opinion subdirectories (log/ and tmp/) when ensure_exists=True.