docs: fix heading levels [ci skip]

Author: azz

README.md

@@ -97,7 +97,7 @@ For example `pretty-quick --pattern "**/*.*(js|jsx)"` or `pretty-quick --pattern
 
 Outputs the name of each file right before it is proccessed. This can be useful if Prettier throws an error and you can't identify which file is causing the problem.
 
-## `--bail`
+### `--bail`
 
 Prevent `git commit` if any files are fixed.