Remove pypi_release as an option (#2508)

Summary:
Pull Request resolved: #2508

release stage already tested pypi as well, remove as option

Reviewed By: iamzainhuda

Differential Revision: D64778003

fbshipit-source-id: 96bddf7254412f5abd78f7b8c204e2ffabf87fb9

.github/workflows/validate-binaries.yml

@@ -23,7 +23,6 @@ on:
           - release
           - nightly
           - test
-          - pypi_release
       ref:
         description: 'Reference to checkout, defaults to empty'
         default: ""