Deploy docs to vercel (#1335)

## Summary
Deploy docs to vercel. This is part of the general move of
www.jetpack.io

## How was it tested?
vercel

Author: LucilleH

.gitignore

@@ -33,3 +33,6 @@ __pycache__/
 
 # test specific files
 .test_tmp_*
+
+# deployment
+.vercel

docs/Dockerfile

@@ -2,5 +2,5 @@
 FROM nginx:stable-alpine as deploy
 WORKDIR /app
 EXPOSE 80
-COPY ./app/build ./static/devbox/docs/
+COPY ./app/build/devbox/docs ./static/devbox/docs/
 COPY ./nginx.conf /etc/nginx/nginx.conf

docs/app/.gitignore

@@ -18,3 +18,4 @@
 npm-debug.log*
 yarn-debug.log*
 yarn-error.log*
+.vercel

docs/app/docs/devbox_global.md

@@ -9,7 +9,7 @@ For example — if you use ripgrep as your preferred search tool, you can add it
 
 <figure>
 
-![Installing ripgrep using `devbox global add ripgrep](../../app/static/img/devbox_global.svg)
+![Installing ripgrep using `devbox global add ripgrep](../static/img/devbox_global.svg)
 
 <figcaption>Installing Packages with Devbox Global</figcaption>
 </figure>

docs/app/package.json

@@ -5,7 +5,8 @@
     "scripts": {
         "docusaurus": "docusaurus",
         "start": "docusaurus start",
-        "build": "docusaurus build",
+        "build": "docusaurus build && yarn run postbuild",
+        "postbuild": "mkdir -p tmp && cp -r build/* tmp/ && mkdir -p build/devbox/docs && cp -r tmp/* build/devbox/docs/ && rm -rf tmp",
         "swizzle": "docusaurus swizzle",
         "deploy": "docusaurus deploy",
         "clear": "docusaurus clear",