feat: add automated builds to branch

Author: laksith19

.github/workflows/build-with-colmena.yml

@@ -0,0 +1,23 @@
+name: Build with Colmena
+
+on:
+  push:
+    branches:
+      - automated_builds
+
+jobs:
+  build_and_deploy:
+
+    runs-on: ubuntu-latest
+
+    steps:
+
+    - name: Checkout
+      uses: actions/checkout@v4
+
+    - name: Install Nix
+      uses: cachix/install-nix-action@v27
+
+    - name: Build with Colmena
+      run: nix develop -c colmena build
+

README.md

@@ -1,5 +1,7 @@
 # nix
 
+[![GitHub Actions Build](https://github.com/ocf/nix/actions/workflows/build-with-colmena.yml/badge.svg)](https://github.com/ocf/nix/actions/workflows/build-with-colmena.yml)
+
 This repository contains the [NixOS] files used to maintain and configure the
 servers and desktops used by the [Open Computing Facility] at UC Berkeley.