Use GitLab CI and drop GitHub CI

.github/workflows/lint.yml

-name: Lint
-
-on:
-  push:
-
-jobs:
-  lint:
-    name: Run lint
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v2
-        with:
-          ref: ${{ github.head_ref }}
-      - uses: actions/setup-python@v2
-        with:
-          python-version: 3.9
-      - name: Install poetry
-        uses: abatilo/actions-poetry@v2.0.0
-      - name: Install dependencies
-        run: pip install tox
-      - name: Lint
-        run: tox -e lint,security

.github/workflows/reformat.yml

-name: Reformat
-
-on:
-  push:
-
-jobs:
-  black:
-    name: Run black/isort
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Checkout code
-        uses: actions/checkout@v2
-        with:
-          ref: ${{ github.head_ref }}
-      - uses: actions/setup-python@v2
-        with:
-          python-version: 3.9
-      - name: Install poetry
-        uses: abatilo/actions-poetry@v2.0.0
-      - name: Install dependencies
-        run: pip install tox
-      - name: Reformat
-        run: tox -e reformat
-      - uses: stefanzweifel/git-auto-commit-action@v4
-        with:
-          commit_message: "Reformat code using black"
-          commit_options: '--no-verify --signoff'
-          file_pattern: "*.py"

.gitlab-ci.yml

+image: "debian:buster"
+
+.before-script: &before-script
+  - apt update && apt install -y python3-setuptools python3-pip python3-dev git
+  - pip3 install poetry tox
+
+before_script:
+  - *before-script
+
+stages:
+  - test
+  - build
+
+lint:
+  stage: test
+  script:
+    - tox -e lint
+
+build-deb:
+  stage: build
+  before_script:
+    - *before-script
+    - apt update && apt install -y build-essential debhelper devscripts equivs dh-virtualenv libffi-dev
+  script:
+    - ./build-deb.sh
+    - mkdir build
+    - mv ../*.deb build/
+
+  artifacts:
+    paths:
+      - build/*
\ No newline at end of file