remove authorization header

Author: ramsessanchez

src/main/java/com/microsoft/graph/core/content/BatchRequestContent.java

@@ -178,6 +178,7 @@ public InputStream getBatchRequestContent() throws IOException {
             return in;
         }
     }
+    private static final String AUTHORIZATION_HEADER_KEY = "authorization";
     private void writeBatchRequestStep(BatchRequestStep requestStep, JsonWriter writer) throws IOException {
             Request request = requestStep.getRequest();
             writer.beginObject();
@@ -208,14 +209,14 @@ private void writeBatchRequestStep(BatchRequestStep requestStep, JsonWriter writ
                     writer.value(rawBodyContent);
                 }
             }
-            // If 'authorization' header is the only header, do not include headers object
-            if(!(headers.names().size() == 1 && headers.names().contains("authorization")) && (headers.size() != 0 || requestBody != null)) {
+            //Remove the header if it is some version of 'authorization'
+            //RemoveAll utilizes ignoreCase natively
+            headers = headers.newBuilder().removeAll(AUTHORIZATION_HEADER_KEY).build();
+            if((headers.size() != 0 || requestBody != null)) {
                     writer.name(CoreConstants.BatchRequest.HEADERS);
                     writer.beginObject();
                     for (int i = 0; i < headers.size(); i++) {
-                        // If multiple headers exist, do not include 'authorization' header
-                        if(!headers.name(i).equals("authorization"))
-                            writer.name(headers.name(i)).value(headers.value(i));
+                        writer.name(headers.name(i)).value(headers.value(i));
                     }
                     writer.endObject();
             }

src/test/java/com/microsoft/graph/core/content/BatchRequestContentTest.java

@@ -6,7 +6,6 @@
 import com.microsoft.graph.core.models.BatchRequestStep;
 import com.microsoft.graph.core.requests.IBaseClient;
 import com.microsoft.kiota.HttpMethod;
-import com.microsoft.kiota.RequestHeaders;
 import com.microsoft.kiota.RequestInformation;
 import com.microsoft.kiota.authentication.AnonymousAuthenticationProvider;
 
@@ -278,7 +277,7 @@ void BatchRequestContent_DoNotAddAuthorizationHeader() throws Exception {
         requestInfo2.pathParameters = pathParameters2;
         requestInfo2.httpMethod = HttpMethod.GET;
         // No headers object should be present in the Json body
-        requestInfo2.headers.add("authorization", longBearerString);
+        requestInfo2.headers.add("AuthoriZation", longBearerString); // Test with strange casing
 
         BatchRequestContent batchRequestContent = new BatchRequestContent(client);
         batchRequestContent.addBatchRequestStep(new BatchRequestStep("1",adapter.convertToNativeRequest(requestInfo)));