refactor(ci): rename: update-flake.yaml -> update.yaml

Author: gekoke

.github/workflows/update-flake.yaml .github/workflows/update.yaml

@@ -1,11 +1,11 @@
-name: update flake.lock
+name: update
 on:
   workflow_dispatch:
   schedule:
     - cron: '0 21 1 * *'
 
 jobs:
-  lockfile:
+  update:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout repository