Remove disk-clean workflow (#30741)

The jobs in the workflow runs in parallel. The `disk-clean` job actually
does nothing, i.e. it will not clean the disk for `nightly-binary`,
`nightly-docker-rootful`, `nightly-docker-rootless`

.github/workflows/disk-clean.yml

@@ -1,25 +0,0 @@
-name: disk-clean
-
-on:
-  workflow_call:
-
-jobs:
-  triage:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v4
-      - name: Free Disk Space (Ubuntu)
-        uses: jlumbroso/free-disk-space@main
-        with:
-          # this might remove tools that are actually needed,
-          # if set to "true" but frees about 6 GB
-          tool-cache: false
-
-          # all of these default to true, but feel free to set to
-          # "false" if necessary for your workflow
-          android: true
-          dotnet: true
-          haskell: true
-          large-packages: false
-          docker-images: false
-          swap-storage: true

.github/workflows/release-nightly.yml

@@ -9,8 +9,6 @@ concurrency:
   cancel-in-progress: true
 
 jobs:
-  disk-clean:
-    uses: ./.github/workflows/disk-clean.yml
   nightly-binary:
     runs-on: nscloud
     steps: