Remove third p from suppport

Co-authored-by: Hugo van Kemenade <1324225+hugovk@users.noreply.github.com>

Author: emmatyping

peps/pep-0778.rst

@@ -177,7 +177,7 @@ the benefits of symlinks in wheels. It is important for installers to give clear
 symlinks are unsupported on the platform, and explain why installation has failed.
 
 For people building libraries, documentation on ``packaging.python.org`` should describe the use
-cases and caveats (especially platform suppport) of symlinks in wheels. Otherwise it should be
+cases and caveats (especially platform support) of symlinks in wheels. Otherwise it should be
 handled transparently by build backends in the same way any normal file would be handled.
 
 Reference Implementation