unix: stop building libedit and ncurses on macOS

Our static-modules files link against the system ncurses. But
we were building a custom ncurses. This could lead to confusion where
our modern ncurses was "leaking" into build state / configuration,
leading to run-time crashes (see #83).

This commit drops building ncurses for macOS.

Because libedit and ncurses are closely related and we were also
linking against the system libedit, we drop building modern libedit
as well.

Author: indygreg

cpython-unix/targets.yml

@@ -82,9 +82,7 @@ aarch64-apple-darwin:
     - '-mmacosx-version-min=11.0'
   needs:
     - bzip2
-    - libedit
     - libffi
-    - ncurses
     - sqlite
     - tcl
     - tk
@@ -467,9 +465,7 @@ x86_64-apple-darwin:
     - '-mmacosx-version-min=10.9'
   needs:
     - bzip2
-    - libedit
     - libffi
-    - ncurses
     - sqlite
     - tcl
     - tk