chore: remove filterSensitiveLog for union service exceptions

Author: trivikr

smithy-typescript-codegen/src/main/java/software/amazon/smithy/typescript/codegen/UnionGenerator.java

@@ -22,6 +22,7 @@
 import software.amazon.smithy.model.Model;
 import software.amazon.smithy.model.shapes.MemberShape;
 import software.amazon.smithy.model.shapes.UnionShape;
+import software.amazon.smithy.model.traits.ErrorTrait;
 import software.amazon.smithy.utils.SmithyInternalApi;
 import software.amazon.smithy.utils.StringUtils;
 
@@ -177,7 +178,9 @@ public void run() {
             writeUnionMemberInterfaces();
             writeVisitorType();
             writeVisitorFunction();
-            writeFilterSensitiveLog();
+            if (!this.shape.hasTrait(ErrorTrait.class)) {
+                writeFilterSensitiveLog();
+            }
             if (includeValidation) {
                 writeValidate();
             }