Add 'often'

Author: martinbonnin

CONTRIBUTING.md

@@ -7,7 +7,7 @@ contributions.
 Contributions that do not change the interpretation of the spec but instead
 improve legibility, fix editorial errors, clear up ambiguity and improve
 examples are encouraged. Those are often referred as "editorial changes" and
-merged by a spec editor with little process.
+often merged by a spec editor with little process.
 
 However, contributions that _do_ meaningfully change the interpretation of the
 spec must follow an RFC (Request For Comments) process led by a _champion_