conda mambabuild installs outdated package from local channel

[aaron-kaplan]

I had a recipe that failed with conda mambabuild but succeeded with conda build. The failure came from the fact that I had an old, buggy version of one of the dependencies in my local channel, and when creating the test environment mambabuild used that buggy version instead of the more recent version available in a remote channel. In contrast, conda build used the remote one, and the tests passed. Once I removed the offending package from my local channel, mambabuild succeeded too.