feat: Replace paru with yay

Paru has not been updated in months and is incompatible with the current
version of pacman / libalpm, which is v16.0.0. See upstream issue [1].

Replace paru with yay so the action works again.

Also updated CI test with latest Spotify as the old version is gone now.

[1] https://github.com/Morganamilo/paru/issues/1454

action.yml

@@ -36,7 +36,7 @@ inputs:
     default: 'true'
     required: false
   aur:
-    description: 'Resolve dependencies using paru'
+    description: 'Resolve dependencies using yay'
     default: 'false'
     required: false
   archlinux_keyring: