echo -n is not portable

[jdugan6240]

Currently, the default starship.toml for kakship uses echo -n for certain modules. This is not posix compliant (it's actually a bash extension) and therefore not portable, and on MacOS for instance, this does not work since /bin/sh is not bash. /bin/echo -n solves this issue on MacOS at least, but that's also a bad idea. printf should be used instead to ensure the default config works everywhere.