Because I was using the Mac OS browser, I ended up having a .DS_Store at ./lib/.DS_Store of a dapptools project. Technically there shouldn't be any .DS_Store files in ./lib. But also dapp test and dapp update should just ignore it
dapp test
dapp-remappings: error: ./lib/.DS_Store is not a Git repository
Because I was using the Mac OS browser, I ended up having a .DS_Store at ./lib/.DS_Store of a dapptools project. Technically there shouldn't be any .DS_Store files in ./lib. But also
dapp test
anddapp update
should just ignore it