Correct code block annotations

Author: mvz

README.md

@@ -240,7 +240,7 @@ UtilityFunction:
 
 For a basic overview, run
 
-```Ruby
+```bash
 reek --help
 ```
 

docs/API.md

@@ -143,7 +143,7 @@ string -- 2 warnings:
 Of course, directory specific configuration and excluded paths are supported as
 well:
 
-```
+```ruby
 config_hash = {
   'IrresponsibleModule' => { 'enabled' => false }
   'spec/samples/three_clean_files/' =>