[DOCS] Documentation needed for Islandora Site Template

[joshdentremont]

Much of the existing Docker documentation is written for Isle-dc, and we are lacking in docs for maintaining a site template site.

I am working on documenting multiple aspects of this, so this issue is just for tracking the overall progress, and any related discussion.

This is also the first step in addressing the issue here: #2273

The items to be documented are:

• Setup - Site Template Setup Documentation #2311
• Modifications - Site Template Customizations Documentation #2312 & Site Template Docker Compose Modifications Documentation #2314
• Docker commands - Site Template Docker Commands Documentation #2313
• Updating Drupal and Buildkit - Site Template Updating Documentation #2315
• Backup and Restore - Site Template back up and restore instructions #2317
• Converting from isle-dc to site template - Instructions to convert isle-dc to site template #2319

[joshdentremont]

We should also document how to upload demo content. I tried updating the instructions from isle-dc, but it kept failing to find my local certificate. I think it's something to do with how we use mkcert to generate certs for islandora.dev. I tried copying them into the container and running update-ca-certificates, but it still gave me this error:

Oops, Workbench can't connect to https://islandora.dev.
Confirm your "host" configuration setting is correct and that the website is running, and try again.
HTTPSConnectionPool(host='islandora.dev', port=443): Max retries exceeded with url: /entity/entity_form_display/node.islandora_object.default?_format=json (Caused by SSLError(SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed: unable to get local issuer certificate (_ssl.c:997)')))

See #2349 for more details.