Update "only-" actions to node20

restore/action.yml

@@ -31,7 +31,7 @@ outputs:
   cache-matched-key:
     description: 'Key of the cache that was restored, it could either be the primary key on cache-hit or a partial/complete match of one of the restore keys'
 runs:
-  using: 'node16'
+  using: 'node20'
   main: '../dist/restore-only/index.js'
 branding:
   icon: 'archive'

save/action.yml

@@ -16,7 +16,7 @@ inputs:
     default: 'false'
     required: false
 runs:
-  using: 'node16'
+  using: 'node20'
   main: '../dist/save-only/index.js'
 branding:
   icon: 'archive'