Add missing app check

functions

@@ -14,9 +14,15 @@ dokku-ansible-deploy-vault-pass-cmd() {
   #shellcheck disable=SC2034
   declare desc="add new app vault password for decryption of passwords"
 
-  local app="$1"
   local vault_file="$DOKKU_LIB_ROOT/data/deploy.d/$app/.vault-password.sh"
 
+  local app="$2"
+
+  if [[ -n "$app" ]]; then
+    dokku_col_log_info1_quiet "missing application name, try 'dokku ansible-deploy:vault-pass myappname'"
+    exit 1
+  fi
+
   if [[ -f $vault_file ]]; then
     dokku_col_log_info1_quiet "Vault password already in place"
     exit 0