3.21.5

Enhancements:

• Revert "Consider any file containing .yaml in its name as maybe a recipe file" (#4235)
• Support setting build/script_env values containing "=" (#4211)
• Drop Python 2.7 support from setup.py (#4202)
• Make variant configuration error message more informative (#4198)
• Ensure file globs are always sorted (#4186)
• Add preliminary support for prelink_message files in conda packages (#4203)

Bug fixes:

• Do not munge rpath for non Mach-O files on macOS (#4238)
• Fix Windows test file extension reported by conda-debug (#4224)

Documentation:

• Document build/script_env recipe option (#4211)
• Clarify wording about selecting multiple operating systems (#4139)

Contributors:

• @chrisburr
• @gabm
• @isuruf
• @jacobtylerwalls
• @katietz
• @kenodegard
• @marcelotrevisani
• @xhochy