ReturnCode always 0 when run against multiple globs

[robellegate]

If you use multiple glob patterns, write-good will always return 0 even if there's grammar mistakes.

This is what happens when using multiple globs, *.md and ./docs/*.md:
Example

$ write-good *.md ./docs/*.md --parse --no-passive --no-adverb --no-tooWordy --no-cliches
README.md:14:29:"various" is a weasel word
README.md:15:6:"and" is repeated






$ echo $?
0

Whereas this is what happens when run with only one glob, *.md:

$ write-good *.md --parse --no-passive --no-adverb --no-tooWordy --no-cliches
README.md:14:29:"various" is a weasel word
README.md:15:6:"and" is repeated
$ echo $?
255

[robellegate]

This is causing issues where the CI/CD pipeline will succeed even when grammar issues are detected

[RichardLitt]

Thanks for pointing this out, @robellegate. A PR fix would be great. :)