CI: Migrate to Github Actions and drop python2

Signed-off-by: Robbie Harwood <rharwood@redhat.com>

Author: frozencemetery

.github/workflows/build.yml

@@ -0,0 +1,36 @@
+{
+    "name": "Build",
+    "on": { "pull_request": null },
+    "jobs": {
+        "linux": {
+            "runs-on": "ubuntu-latest",
+            "strategy": {
+                "fail-fast": false,
+                "matrix": {
+                    "python": [
+                        "3.6",
+                        "3.7",
+                        "3.8",
+                        "3.9",
+                    ],
+                },
+            },
+            "steps": [
+                { "uses": "actions/checkout@v2" },
+                {
+                    "uses": "actions/setup-python@v2",
+                    "with": { "python-version": "${{ matrix.python }}"},
+                },
+                { "run": "sudo apt update" },
+                { "run": "sudo apt install -y libkrb5-dev" },
+                { "run": "pip install flake8 mock" },
+                { "run": "pip install -r requirements.txt" },
+                { "run": "python3 -m unittest" },
+                {
+                    "run": "flake8",
+                    "if": "${{ matrix['python'] == 3.9 }}",
+                },
+            ],
+        },
+    },
+}