Improve README

[ccaAV]

Hello,

I am trying to run the project with the docker file. I have not been able to run docker-compose up. So far I have had the following errors:

• the env.local and env.prod.local files were missing. I have noticed from the .env file comments that I could copy .env to create those files, but maybe they should be created by default or instructions added to the README
• I am not sure whether I should modify the .env files, and if I should, I am not sure what to modify it with.
• Not modifying the .env.local and .env.prod.local files (only copying them from .env) and running docker-compose up I run into this error: failed to solve: rpc error: code = Unknown desc = failed to solve with frontend dockerfile.v0: failed to create LLB definition: target stage symfony_php_dev could not be found. This error seems to come from the fact that symfony_php_dev is commented out in the Dockerfile
• in .env.local , MVOAS_MYSQL_PASSWORD has to be defined. This should be mentioned in the README

There might be other issues, or I may not be fixing mine correctly, but ideally all the information necessary to set up the project in docker should be included in the README. The easier it is to get started, the more likely people will be using this

[domi41]

Thank you for the feedback ! I will edit the README to clarify this.