Document prerequisites for Docker Compose support

[mhalbritter]

We should document what the minimum version of Docker and Docker Compose for our Docker Compose support is.

[mhalbritter]

Tested some Docker Compose versions:

• 2.0.0: fails unknown flag: --wait
• 2.1.0: fails unknown flag: --wait
• 2.2.0: works
• v2.23.3: works
• v2.24.0-birthday.10: works

So the minimum Docker Compose version is 2.2.0.