chore(codegen): remove redundant checks for ifPresent

Author: trivikr

codegen/smithy-aws-typescript-codegen/src/main/java/software/amazon/smithy/aws/typescript/codegen/AddHttpChecksumDependency.java

@@ -28,6 +28,7 @@
 import software.amazon.smithy.codegen.core.SymbolProvider;
 import software.amazon.smithy.model.Model;
 import software.amazon.smithy.model.knowledge.TopDownIndex;
+import software.amazon.smithy.model.shapes.MemberShape;
 import software.amazon.smithy.model.shapes.OperationShape;
 import software.amazon.smithy.model.shapes.ServiceShape;
 import software.amazon.smithy.model.shapes.StructureShape;
@@ -203,13 +204,14 @@ private static Map<String, Object> getPluginFunctionParams(
         params.put("requestChecksumRequired", httpChecksumTrait.isRequestChecksumRequired());
         httpChecksumTrait.getRequestAlgorithmMember().ifPresent(requestAlgorithmMember -> {
             params.put("requestAlgorithmMember", requestAlgorithmMember);
-            operation.getInput().ifPresent(inputShapeId -> {
-                StructureShape inputShape = model.expectShape(inputShapeId, StructureShape.class);
-                inputShape.getMember(requestAlgorithmMember).ifPresent(requestAlgorithmMemberShape -> {
-                    requestAlgorithmMemberShape.getTrait(HttpHeaderTrait.class).ifPresent(httpHeaderTrait -> {
-                        params.put("requestAlgorithmMemberHttpHeader", httpHeaderTrait.getValue());
-                    });
-                });
+
+            // We know that input shape is structure, and contains requestAlgorithmMember.
+            StructureShape inputShape =  model.expectShape(operation.getInput().get(), StructureShape.class);
+            MemberShape requestAlgorithmMemberShape = inputShape.getAllMembers().get(requestAlgorithmMember);
+
+            // Set requestAlgorithmMemberHttpHeader if HttpHeaderTrait is present.
+            requestAlgorithmMemberShape.getTrait(HttpHeaderTrait.class).ifPresent(httpHeaderTrait -> {
+                params.put("requestAlgorithmMemberHttpHeader", httpHeaderTrait.getValue());
             });
         });
         httpChecksumTrait.getRequestValidationModeMember().ifPresent(requestValidationModeMember -> {