prettier creates a node_modules folder when formatting some files, which
it should not as cache is not enabled. Setting the cache to a file works
around this.
See https://github.com/prettier/prettier/issues/13032
The fact it uses bash is an implementation detail. Update the
documentation to state that the input is a file name glob rather than a
bash case match. Updates the default formatters to not rely on being a
bash case statement.