Customize: Consistently use `input_attrs` as control param key in JS instead of `inputAttrs`.

See #30738, #41897.


git-svn-id: https://develop.svn.wordpress.org/trunk@41936 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/js/customize-controls.js

@@ -6900,7 +6900,7 @@
 				type: 'button',
 				section: section.id,
 				priority: 30,
-				inputAttrs: {
+				input_attrs: {
 					'class': 'button-link button-link-delete',
 					value: api.l10n.discardChanges
 				}

src/wp-includes/class-wp-customize-manager.php

@@ -4003,7 +4003,7 @@ final class WP_Customize_Manager {
 					if ( data.description ) {
 						inputAttrs['aria-describedby'] = descriptionId;
 					}
-					_.extend( inputAttrs, data.inputAttrs );
+					_.extend( inputAttrs, data.input_attrs );
 					#>
 
 					<# if ( 'button' === data.type ) { #>