CI: Add forgejo CI

Signed-off-by: Vasiliy Doylov <nekocwd@mainlining.org>

.forgejo/workflows/build-alpine.yaml

@@ -0,0 +1,31 @@
+name: PostmarketOS Build
+run-name: PostmarketOS Build
+on:
+  push:
+  workflow_dispatch:
+
+jobs:
+  build:
+    runs-on: Pmbootstrap
+    strategy:
+      matrix:
+        info:
+          - arch: aarch64
+          - arch: x86_64
+    name: Build for ${{ matrix.info.arch }}
+    steps:
+      - name: Check out repository code
+        uses: actions/checkout@v4
+      - name: Build package
+        id: build
+        uses: actions/pmbootstrap-build@main
+        with:
+          name: pipetap
+          aports: ${{github.workspace}}/misc/alpine
+          arch: ${{ matrix.info.arch }}
+          src: ${{github.workspace}}
+      - name: "Upload packages"
+        uses: actions/upload-alpine-package@main
+        with:
+          files: ${{steps.build.outputs.packages}}
+          secret: ${{secrets.PACKAGE_TOKEN}}