Remove precache until we have it enabled

.github/workflows/codespaces.yaml

@@ -1,19 +0,0 @@
-name: prebuild codespace
-on:
-  push:
-    branches:
-    - master
-    - codespaces-sandbox
-  workflow_dispatch: 
-
-jobs:
-  createPrebuild:
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@v2
-    - uses: github/codespaces-precache@v1-stable
-      with:
-        regions: WestUs2 EastUs WestEurope SouthEastAsia
-        sku_name: premiumLinux
-      env:
-        GITHUB_TOKEN: ${{secrets.GITHUB_TOKEN}}