Use WarpBuild runners for CI workflows (#185)

Migrate test, integration, and docker workflows from ubuntu-latest to
warp-ubuntu-latest-x64-4x. Update Docker Buildx setup with
network=host driver-opts and point Docker layer cache at WarpBuild's
cache proxy. Release and CLA workflows are left on GitHub-hosted
runners.

Author: tillrohrmann

.github/workflows/docker.yml

@@ -15,7 +15,7 @@ env:
 
 jobs:
   build-python-services-docker-image:
-    runs-on: ubuntu-latest
+    runs-on: warp-ubuntu-latest-x64-4x
     steps:
       - name: Checkout repository
         uses: actions/checkout@v4
@@ -24,7 +24,10 @@ jobs:
         uses: docker/setup-qemu-action@v2
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@v2
+        uses: docker/setup-buildx-action@v3
+        with:
+          driver-opts: |
+            network=host
 
       - name: Log into GitHub container registry
         uses: docker/login-action@v2

.github/workflows/integration.yaml

@@ -46,7 +46,7 @@ on:
 jobs:
   sdk-test-suite:
     if: github.repository_owner == 'restatedev'
-    runs-on: ubuntu-latest
+    runs-on: warp-ubuntu-latest-x64-4x
     name: Features integration test
     permissions:
       contents: read
@@ -104,6 +104,9 @@ jobs:
       - name: Set up Docker Buildx
         if: ${{ inputs.serviceImage == '' }}
         uses: docker/setup-buildx-action@v3
+        with:
+          driver-opts: |
+            network=host
       - name: Build Python test-services image
         if: ${{ inputs.serviceImage == '' }}
         id: build
@@ -114,8 +117,8 @@ jobs:
           push: false
           load: true
           tags: restatedev/test-services-python
-          cache-from: type=gha,scope=${{ github.workflow }}
-          cache-to: type=gha,mode=max,scope=${{ github.workflow }}
+          cache-from: type=gha,url=http://127.0.0.1:49160/,version=1,scope=${{ github.workflow }}
+          cache-to: type=gha,url=http://127.0.0.1:49160/,mode=max,version=1,scope=${{ github.workflow }}
 
       # Or use the provided one
       - name: Pull test services image

.github/workflows/test.yml

@@ -15,7 +15,7 @@ permissions:
 jobs:
   lint-and-test:
     name: "Lint and Test (Python ${{ matrix.python }})"
-    runs-on: ubuntu-latest
+    runs-on: warp-ubuntu-latest-x64-4x
     strategy:
       matrix:
         python: [ "3.10", "3.11", "3.12", "3.13", "3.14" ]