Only check for pw(q)gen if we're tryna use them

Ref #147

abra

@@ -1632,12 +1632,17 @@ sub_app_secret_generate(){
   fi
 
   if [[ -n "$LENGTH" ]]; then
-    require_binary pwgen
-    PWGEN=${abra__cmd_:-pwgen -s "$LENGTH" 1}
+    if [ -z "$abra__cmd_" ]; then
+      require_binary pwgen
+      abra__cmd_="pwgen -s \"$LENGTH\" 1"
+    fi
   else
-    require_binary pwqgen
-    PWGEN="${abra__cmd_:-pwqgen}"
+    if [ -z "$abra__cmd_" ]; then
+      require_binary pwqgen
+      abra__cmd_=pwqgen
+    fi
   fi
+  PWGEN=${abra__cmd_}
 
   debug "SECRET: $SECRET, VERSION $VERSION, PW $PWGEN, ALL $abra___all"