Run recipe tests using UML on GitHub actions

Running the tests on the host is a good first step; to test Debos
properly we should run inside a Fakemachine. Since GitHub actions
do not support creating nested virtual machines, use the
user-mode-linux backend in Fakemachine to create a user process
to run the tests inside of.

Since Docker autobuild does not support UML the docker-compose
file purposely does not have a suffix of `.test.yml` so that the
test will not be picked up to run on Docker autobuild.

Signed-off-by: Christopher Obbard <chris.obbard@collabora.com>

.github/workflows/build-test.yaml

@@ -22,3 +22,8 @@ jobs:
         run: |
           docker-compose -f docker/recipes.test.yml \
             up --build --exit-code-from=sut
+
+      - name: Run test recipes using UML backend
+        run: |
+          docker-compose -f docker/recipes-test-uml.yml \
+            up --build --exit-code-from=sut

docker/README.md

@@ -39,3 +39,8 @@ Run test recipes on host:
 ```
 docker-compose -f docker/recipes.test.yml up --build --exit-code-from=sut
 ```
+
+Run test recipes using UML backend:
+```
+docker-compose -f docker/recipes-test-uml.yml up --build --exit-code-from=sut
+```

docker/recipes-test-uml.yml

@@ -0,0 +1,23 @@
+version: '3.6'
+
+services:
+  sut:
+    build:
+      context: ..
+      dockerfile: docker/Dockerfile
+      target: runner
+    volumes:
+      - type: bind
+        source: ../tests
+        target: /recipes
+    tmpfs:
+      - /scratch:exec
+    environment:
+      - TMP=/scratch
+    cap_add:
+      - SYS_PTRACE
+    security_opt:
+      - label:disable
+    working_dir: /recipes
+    entrypoint: ./tests.sh
+    command: --fakemachine-backend=uml