[3.12] gh-112431: Unconditionally call hash -r (GH-112432) (GH-112493)

gh-112431: Unconditionally call `hash -r` (GH-112432)

The `activate` script calls `hash -r` in two places to make sure the shell picks
up the environment changes the script makes. Before that, it checks to
see if the shell running the script is bash or zsh.

`hash -r` is specified by POSIX and is not exclusive to bash and zsh.
This guard prevents the script from calling `hash -r` in other
`GH-!/bin/sh`-compatible shells like dash.
(cherry picked from commit a194938)

Co-authored-by: James Morris <6653392+J-M0@users.noreply.github.com>

Author: miss-islington

Lib/venv/scripts/common/activate

@@ -14,12 +14,9 @@ deactivate () {
         unset _OLD_VIRTUAL_PYTHONHOME
     fi
 
-    # This should detect bash and zsh, which have a hash command that must
-    # be called to get it to forget past commands.  Without forgetting
+    # Call hash to forget past commands. Without forgetting
     # past commands the $PATH changes we made may not be respected
-    if [ -n "${BASH:-}" -o -n "${ZSH_VERSION:-}" ] ; then
-        hash -r 2> /dev/null
-    fi
+    hash -r 2> /dev/null
 
     if [ -n "${_OLD_VIRTUAL_PS1:-}" ] ; then
         PS1="${_OLD_VIRTUAL_PS1:-}"
@@ -68,9 +65,6 @@ if [ -z "${VIRTUAL_ENV_DISABLE_PROMPT:-}" ] ; then
     export VIRTUAL_ENV_PROMPT
 fi
 
-# This should detect bash and zsh, which have a hash command that must
-# be called to get it to forget past commands.  Without forgetting
+# Call hash to forget past commands. Without forgetting
 # past commands the $PATH changes we made may not be respected
-if [ -n "${BASH:-}" -o -n "${ZSH_VERSION:-}" ] ; then
-    hash -r 2> /dev/null
-fi
+hash -r 2> /dev/null