It seems impossible to prevent brew updating everything, with a disastrous consumption of credits. The documentation says it won’t update “by default”, but it does so, even when asked nicely not to.
The homebrew section is:
addons: homebrew: update: false taps: - homebrew/cask-versions # for openjdk packages: - ant - openjdk@8
This may be new-ish behaviour. Or is it related to a change in the particular dependencies I need? I am running on Xcode11.6.
The build works, it just takes 19 minutes of which this is 17 I could do without: