Update github test workflow to current (#16)

.github/workflows/tests.yml

@@ -18,6 +18,10 @@ defaults:
   run:
     shell: bash
 
+# This is required for "gautamkrishnar/keepalive-workflow"
+permissions:
+  contents: write
+
 env:
   NIGHTLY_DDEV_PR_URL: "https://nightly.link/ddev/ddev/actions/runs/1720215802/ddev-linux-amd64.zip"
   # Allow ddev get to use a github token to prevent rate limiting by tests
@@ -40,7 +44,9 @@ jobs:
 
     steps:
     - uses: actions/checkout@v2
-    - run: echo "/home/linuxbrew/.linuxbrew/bin:/home/linuxbrew/.linuxbrew/sbin" >> $GITHUB_PATH
+    - name: Set up Homebrew
+      id: set-up-homebrew
+      uses: Homebrew/actions/setup-homebrew@master
     - name: Environment setup
       run: |
         brew install bats-core mkcert