Align protocol test query param logic with APIG behavior

We use APIGateway multi-value query parameters which will always use an array
value for query parameters, even if they're specified only once, and even if
that single specification does not have a value. Our translation logic from
APIG preserves this structure, and since all query parameters can have multiple
values, this isn't necessarily wrong. Our handling of query parameters is
actually broken in main, but protocol tests don't uncover this due to the logic
that generates non-array values for single query parameters. Streamlining our
generated requests in protocol tests uncovers this bug, and aligns more closely
with how our code runs in the wild.

Author: adamthom-amzn

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

@@ -449,13 +449,7 @@ private ObjectNode buildQueryBag(List<String> queryParams) {
 
         ObjectNode.Builder nodeBuilder = ObjectNode.objectNodeBuilder();
         for (Map.Entry<String, List<String>> entry : query.entrySet()) {
-            // The value of the query bag can either be a single string or a list, so we need to ensure individual
-            // values are written out as individual strings.
-            if (entry.getValue().size() == 1) {
-                nodeBuilder.withMember(entry.getKey(), StringNode.from(entry.getValue().get(0)));
-            } else {
-                nodeBuilder.withMember(entry.getKey(), ArrayNode.fromStrings(entry.getValue()));
-            }
+            nodeBuilder.withMember(entry.getKey(), ArrayNode.fromStrings(entry.getValue()));
         }
         return nodeBuilder.build();
     }