Adds semicolon, closes #3296

Author: JJ

doc/Language/grammars.pod6

@@ -377,7 +377,7 @@ say GrammarAdvice.subparse("use tokens for insignificant whitespace by default")
 say GrammarAdvice.subparse("use regexes for insignificant whitespace by default");
 # OUTPUT: «use regexes for insignificant whitespace by default»
 
-say GrammarAdvice.subparse("use regexes for significant whitespace by default")
+say GrammarAdvice.subparse("use regexes for significant whitespace by default");
 # OUTPUT: #<failed match>
 =end code