Simplify guard against an unavailable AUR

bin/omarchy-pkg-aur-accessible

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+curl -sf --connect-timeout 30 -A "omarchy-update" \
+  "https://aur.archlinux.org/rpc/?v=5&type=info&arg=base" |
+  jq -e empty >/dev/null