Add check for dist folder

.github/workflows/ci.yml

@@ -7,6 +7,13 @@ on:
   workflow_dispatch:
 
 jobs:
+  check-dist-up-to-date:
+    name: Check the dist/ folder is up to date
+    runs-on: ubuntu-22.04
+    steps:
+      - uses: actions/checkout@v3
+      - run: npm run all
+      - run: test $(git status --porcelain=v1 2>/dev/null | wc -l) -eq 0
   run-x86_64-linux:
     name: Run x86_64 Linux
     runs-on: ubuntu-22.04

CONTRIBUTING.md

@@ -0,0 +1,3 @@
+# Submitting Pull Requests
+
+This action is based off https://github.com/actions/javascript-action. As part of your contributing flow you **must** run `npm run all` before we can merge.