update utl for download of docker container

[GavinHuttley]

https://github.com/cogent3/SMBE2024Workshop/wiki/download-the-workshop-environment

[khiron]

Changed the instructions to use git to clone this repo locally (HTTPS:// protocol) or download from the github zip and unpack.

Only wrinkle here is that that creates the folder on the users PC with SMBE2024WORKSHOP and we might want to brand it with cogent3 so they know what it is later when looking at what they did during the workshops.

We can make a bespoke zip named cogent3_2024_workshop like we did for phylomania but that turned out to be a pain as we were adding data to it on the fly as new workshops were being created.