Add release workflow

Author: fingolfin

.github/workflows/release.yml

@@ -0,0 +1,40 @@
+name: Release
+
+# Trigger the workflow on push or pull request
+on:
+  workflow_dispatch:
+    inputs:
+      dry-run:
+        description: "Do not upload the release to GitHub"
+        type: boolean
+        required: false
+        default: false
+
+permissions: write-all
+
+jobs:
+  release:
+    name: "Release the GAP package"
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v5
+      - uses: gap-actions/setup-gap@v2
+        with:
+          GAP_PKGS_TO_BUILD: json
+      - uses: gap-actions/build-pkg-docs@v1
+        with:
+          use-latex: true
+          warnings-as-errors: false
+          # Disable warnings as we we get errors triggered by the GAP
+          # reference manual and I have no idea what causes them or how to
+          # deal with them. E.g.:
+          #
+          #     Section: "ref:specialpcgs" already defined as: 45.13.0
+          #     Now being redefined as: 45.13.2
+
+      - uses: gap-actions/release-pkg@v1
+        with:
+          dry-run: ${{ inputs.dry-run }}
+      - uses: gap-actions/update-gh-pages@v1
+        if: ${{ !inputs.dry-run }}