fix(carbon): make the subform title element larger

Author: skateman

packages/carbon-component-mapper/src/files/sub-form.js

@@ -35,7 +35,7 @@ SubForm.propTypes = {
 };
 
 SubForm.defaultProps = {
-  TitleElement: 'h5',
+  TitleElement: 'h3',
   DescriptionElement: 'p'
 };
 

packages/react-renderer-demo/src/doc-components/examples-texts/carbon/sub-form.md

@@ -2,7 +2,7 @@
 
 |Props|Description|default|
 |-----|-----------|-------|
-|TitleElement|Element wrapping title|h5|
+|TitleElement|Element wrapping title|h3|
 |TitleProps|Props passed to the element wrapping title|{}|
 |DescriptionElement|Element wrapping description|p|
 |DescriptionProps|Props passed to the element wrapping description|{}|