Fix word detection at end of line

[chalin]

• Fixes Mis-capitalized word not detected at end of line in markdown file #71
• Adds a test case that fails without the fix in this PR, but passes otherwise.
• TL;DR Textlint string nodes can contain multiple lines (i.e., \n characters), as you can see from this textlint AST explorer snippet. Hence the regex match in getExactMatchRegExp() should use the m modifier, it would seem.

/cc @svrnm @cartermp

[chalin]

FYI, this fix catches quite a few more issues; e.g., see:

• [CI] Terminology fixes from patched terminology textlint rule open-telemetry/opentelemetry.io#3496

[sapegin]

Thanks for the fix!

[sapegin]

🎉 This PR is included in version 4.0.1 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot 📦🚀

[chalin]

\o/

Thanks for putting out a release so quickly! ✨