chore: implement simple workflow to build project

Author: GROOOOAAAARK

.github/workflows/zig.yml

@@ -0,0 +1,17 @@
+name: Build
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+    branches:
+      - main
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: mlugg/setup-zig@v1
+      - run: zig build