Update overrides-gitpod for solr support

[froboy]

fixes #1678 with great thanks to @sean-e-dietrich in Slack

To test:

• Set up a gitpod project with Solr
• Check the Remote Explorer
• Observe port 8983 has a service available
• Click "Open Browser" and observe the Solr UI is accessible.
  

[sean-e-dietrich]

The problem I can see with this is that if solr does not exist this will throw some errors and the whole stack won't start. Ideally we would turn this into part of the documentation as Solr won't be the only thing we'd need to access the web interface for.

[froboy]

@sean-e-dietrich that makes sense. I've been thinking on it and I'm wondering where it'd go though. Is there support for other docksal-*.[env|yml] files similar to docksal-local.[env|yml]? So like, we'd only want this to load in a gitpod environment, so it'd need to be in something like docksal-gitpod.yml?

[froboy]

I tried creating .docksal/stacks/overrides-gitpod.yml in my project and that didn't take. It seems like #1558 might be related.

Instead, I'm thinking writing to .docksal/docksal-local.yml in the gitpod init process might be the best way to get that config into the environment.

tee -a ./.docksal/docksal-local.yml <<EOF
services:
  solr:
    ports:
      - "8983:8983"
    labels:
      - io.docksal.virtual-host=8983-${GITPOD_WORKSPACE_ID}.${GITPOD_WORKSPACE_CLUSTER_HOST}
EOF

depending on the complexity of your setup, a few options come to mind:

• putting this directly into the .gitpod.yml init task
• a fin command that gets run in the Gitpod init
• a file like gitpod-docksal-local.yml in .docksal/files that gets copied or appended to .docksal/docksal-local.yml in the gitpod init.