Requirements_cache shouldn't create a cache folder when skipped. (#31961

)

* If the requirements cache is skipped then we shouldn't generate a requirements_cache folder.

* pre-commit

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Co-authored-by: eddiephillips <eddiephillips@google.com>

sdks/python/apache_beam/runners/portability/stager.py

@@ -214,7 +214,8 @@ def create_job_resources(options,  # type: PipelineOptions
           os.path.join(tempfile.gettempdir(), 'dataflow-requirements-cache') if
           (setup_options.requirements_cache is None) else
           setup_options.requirements_cache)
-      if not os.path.exists(requirements_cache_path):
+      if (setup_options.requirements_cache != SKIP_REQUIREMENTS_CACHE and
+          not os.path.exists(requirements_cache_path)):
         os.makedirs(requirements_cache_path)
 
       # Stage a requirements file if present.