Add GHA workflow

.github/workflows/test.yml

@@ -0,0 +1,30 @@
+name: CI
+
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+    branches:
+      - '**'
+
+jobs:
+  test:
+    name: Run learn-ocaml on the corpus
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        server_image:
+          - 'ocamlsf/learn-ocaml:0.15.0'
+          # TODO: Keep up-to-date
+          - 'ocamlsf/learn-ocaml:master'
+    steps:
+      - name: Check out the repo
+        uses: actions/checkout@v3
+      - name: Create directory www
+        run: |
+          mkdir -m 755 www
+          sudo chown -v 1000:1000 www
+      - name: Run learn-ocaml on the corpus
+        run: 'docker run --rm -v "$PWD:/repository" -v "$PWD/www:/home/learn-ocaml/www" ${{ matrix.server_image }} build'

README.md

@@ -1 +1,3 @@
 # The Learn OCaml Corpus
+
+[![CI](https://github.com/ocaml-sf/learn-ocaml-corpus/actions/workflows/test.yml/badge.svg?branch=master)](https://github.com/ocaml-sf/learn-ocaml-corpus/actions/workflows/test.yml)