Update release pipelines to upload release artifacts

.github/workflows/release-appimage.yml

@@ -0,0 +1,29 @@
+name: Release (AppImage)
+on:
+  release:
+    types:
+    - created
+jobs:
+  appimage:
+    name: Build AppImage
+    runs-on: ubuntu-latest
+    container: docker
+    steps:
+    - name: Checkout
+      uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+    - name: Build
+      run: |
+        docker build -t appimage-builder . -f burrow-gtk/build-aux/Dockerfile
+        docker create --name temp appimage-builder
+        docker cp temp:/app/burrow-gtk/build-appimage/Burrow-x86_64.AppImage .
+        docker rm temp
+    - name: Upload to GitHub
+      uses: SierraSoftworks/gh-releases@v1.0.7
+      with:
+        token: ${{ secrets.GITHUB_TOKEN }}
+        release_tag: ${{ github.ref_name }}
+        overwrite: 'true'
+        files: |
+          Burrow-x86_64.AppImage