Switch CI to Actions and use Goreleaser (#536)

Reviewed-on: https://gitea.com/gitea/tea/pulls/536
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: techknowlogick <techknowlogick@gitea.io>
Co-committed-by: techknowlogick <techknowlogick@gitea.io>

.gitea/workflows/release-nightly.yml

@@ -0,0 +1,37 @@
+name: goreleaser
+
+on:
+  push:
+    branches: [ main ]
+
+jobs:
+  goreleaser:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+      - run: git fetch --force --tags
+      - name: setup go
+        uses: https://github.com/actions/setup-go@v4
+        with:
+          go-version: '>=1.20.1'
+      - name: import gpg
+        uses: https://github.com/crazy-max/ghaction-import-gpg@v5
+        with:
+          gpg_private_key: ${{ secrets.GPGSIGN_KEY }}
+          passphrase: ${{ secrets.GPGSIGN_PASSPHRASE }}
+      - name: goreleaser
+        uses: https://github.com/goreleaser/goreleaser-action@v4
+        with:
+            distribution: goreleaser-pro
+            version: latest
+            args: release --nightly
+        env:
+          GORELEASER_KEY: ${{ secrets.GORELEASER_KEY }}
+          AWS_REGION: ${{ secrets.AWS_REGION }}
+          AWS_ACCESS_KEY_ID: ${{ secrets.AWS_KEY_ID }}
+          AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
+          S3_REGION: ${{ secrets.AWS_REGION }}
+          S3_BUCKET: ${{ secrets.AWS_BUCKET }}
+          GPGSIGN_PASSPHRASE: ${{ secrets.GPGSIGN_PASSPHRASE }}