sh.zio.backup: add check to make sure mountpoint is ready

usr/local/bin/sh.zio.backup

@@ -323,6 +323,12 @@ elif [[ "$1" == "toggle-mount" ]]; then
     else
         say info "Mounting: $restic_mount_path"
         invoke_restic mount "$restic_mount_path" &>/dev/null & disown;
+
+        while true; do
+            if [[ $(test_restic_mount) == 0 ]]; then
+                say "Mountpoint ready at '$restic_mount_path'"
+            fi
+        done
     fi
 else
     command="$1"