ci: add homebrew github action

.github/workflows/homebrew.yml

@@ -0,0 +1,29 @@
+name: Update Homebrew Formula
+
+on:
+  push:
+    branches:
+      - master
+    tags: 
+      - 'v[0-9]+.[0-9]+.[0-9]+'
+
+jobs:
+  update-formula:
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Check out code
+      uses: actions/checkout@v3
+
+    - name: Update Homebrew Formula
+      run: sed -i '' 's/:tag => "[^"]*"/:tag => "${{  github.ref_name }}"/' ./Formula/renterd.rb
+
+    - name: Create Pull Request
+      uses: peter-evans/[email protected]
+      with:
+        token: ${{ secrets.HOMEBREW_CREATE_PR }}
+        commit-message: Update renterd formula to ${{  github.ref_name }}"
+        title: 'Update renterd formula to ${{  github.ref_name }}'
+        body: 'This is an automated PR to update the formula'
+        branch: bot/update-renterd
+        base: master