Remove unnecessary shape

Author: jterapin

gems/smithy-schema/spec/support/schema_helper.rb

@@ -100,10 +100,7 @@ def sample_shapes
         'smithy.ruby.tests#Union' => {
           'type' => 'union',
           'members' => {
-            'string' => {
-              'target' => 'smithy.api#String',
-              'traits' => { 'smithy.api#jsonName' => 'jsonName' }
-            },
+            'string' => { 'target' => 'smithy.api#String'},
             'structure' => { 'target' => 'smithy.ruby.tests#Structure' },
             'unit' => { 'target' => 'smithy.api#Unit' }
           }