Add a Github Action workflow to run CI checks

I can't really test this, but I think it ought to work. This
should run the container unit tests, pylint, and flake8 checks
on each pull request.

This also removes .travis.yml, as we clearly haven't used travis
for about a decade at this point.

Signed-off-by: Adam Williamson <[email protected]>

Author: AdamWill

.github/workflows/ci.yml

@@ -0,0 +1,41 @@
+---
+name: Run CI checks
+
+on: [pull_request]
+
+jobs:
+  unittests-fedora:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout the repo
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Install make and docker
+        run: apt-get install make docker docker.io
+      - name: Run the tests
+        run: make container-unittests-fedora
+  unittests-el7:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout the repo
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Install make and docker
+        run: apt-get install make docker
+      - name: Run the tests
+        run: make container-unittests-el7
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout the repo
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+      - name: Install make, pylint and flake8
+        run: apt-get install make pylint flake8
+      - name: Run pylint
+        run: make pylint
+      - name: Run flake8
+        run: make flake8