Change syntax for suffix file-types configurations (#4414)

The change in d801a6693c3d475b3942f705d3ef48d7966bdf65 to search for
suffixes in `file-types` is too permissive: files like the tutor or
`*.txt` files are now mistakenly interpreted as R or perl,
respectively.

This change changes the syntax for specifying a file-types entry that
matches by suffix:

```toml
file-types = [{ suffix = ".git/config" }]
```

And changes the file-type detection to first search for any non-suffix
patterns and then search for suffixes only with the file-types entries
marked explicitly as suffixes.

0 files changed, 0 insertions, 0 deletions