check/name/ascii_only_entries: Improve FAIL message

[m4rc1e]

For com.google.fonts/check/name/ascii_only_entries, we have the following fail message:

There are N strings containing non-ASCII characters in the ASCII-only NAME table entries.

It would be great if the message could tell users which name record is at fault and what the characters are. Even better would be displaying a string segment.

Found in issue, magictype/goldman#1 (comment)

[felipesanches]

these strings are actually printed as INFO messages. Perhaps you don't see them because you filtered-out INFO messages.

[felipesanches]

I will change the "bad-string" messages to FAIL-level so that you will always see them.