Consider removing/cutting down further the section on architecture from the intro to project

[anenadic]

In https://carpentries-incubator.github.io/python-intermediate-development/11-software-project/index.html.

Move some of the text to Section 3 / architecture section.

Blocked / to be done after PR #297 is merged.

[anenadic]

This will be fixed with PR #333.

[anenadic]

Closed via #297 and #333.