Add test workflow and badge

.github/workflows/test.yml

@@ -0,0 +1,20 @@
+name: Test
+
+on: [push]
+
+jobs:
+  test:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        go: ["1.20"]
+        os: [ubuntu-latest]
+    name: ${{ matrix.os }} Go ${{ matrix.go }} Tests
+    steps:
+      - uses: actions/checkout@v3
+      - name: Setup go
+        uses: actions/setup-go@v3
+        with:
+          go-version: ${{ matrix.go }}
+      - run: go test

README.md

@@ -2,6 +2,8 @@
 
 Experimental alternative to HTML
 
+![Test](https://github.com/radulucut/htnoml/actions/workflows/test.yml/badge.svg)
+
 ### Example
 
 ```htnoml