bin/lesson_check.py: avoid inconsistent grammar

Pull Request: carpentries/styles#396

diff --git a/bin/lesson_check.py b/bin/lesson_check.py
index 84c28f37c5300fea1e065f1be06196b60cc4db7f..b0b5581a247d2983f78cc63279f2069464035379 100755 (executable)
--- a/bin/lesson_check.py
+++ b/bin/lesson_check.py
@@ -342,7 +342,7 @@ class CheckBase:
                 n > MAX_LINE_LEN) and (not l.startswith('!'))]
             self.reporter.check(not over,
                                 self.filename,
-                                'Line(s) are too long: {0}',
+                                'Line(s) too long: {0}',
                                 ', '.join([str(i) for i in over]))
 
     def check_trailing_whitespace(self):