Serve JBrowse static files from collaboration server

[garrettjstevens]

• In .env file, specify JBROWSE_DIRECTORY as a directory where JBrowse Web is installed.
• If the collaboration server detects a problem with the JBrowse installation (e.g. directory doesn't exist, index.html does not exist in the directory, etc.), the collaboration server quits with an error message that describes how to set up JBrowse.
• In app.module.ts, use ServeStaticModule to serve the JBROWSE_DIRECTORY.
• If you're inside the Apollo repository directory, you can use yarn dlx @jbrowse/cli create myDirectory to add the JBrowse static files to myDirectory.

[garrettjstevens]

I researched a bit and found out about possible performance bottlenecks using this strategy, so let's put this on hold for now while we decide if we still want to do this.

[garrettjstevens]

We've decided against this, due to the performance bottlenecks mentioned. The recommended way to serve JBrowse for Apollo 3 is a static file server like Apache or Nginx.