fix(gpg): remove --pinentry-mode loopback from key import

loopback mode corrupts the at-rest storage of passphrase-less cv25519
secret keys under GnuPG 2.4.x: the keygrip is listed as present but
unusable for pkdecrypt, so pillar decryption fails at render time with
"Bad secret key" while the master still starts cleanly. loopback does
not bypass gpg-agent and is pointless for passphrase-less keys;
--batch --no-tty already covers the non-interactive CI case.

Author: cdalvaro

assets/runtime/functions.sh

@@ -556,9 +556,7 @@ function _setup_gpgkeys() {
   chmod 700 "${SALT_GPGKEYS_DIR}"
 
   local GPG_COMMON_OPTS=(
-    --no-tty
-    --batch                         # non-interactive mode
-    --pinentry-mode loopback        # do not use gpg-agent
+    --no-tty --batch # non-interactive mode
     --homedir="${SALT_GPGKEYS_DIR}"
   )