Fixes empty content type during upload

src/ContentMessages.ts

@@ -303,6 +303,7 @@ export async function uploadFile(
             progressHandler,
             abortController,
             includeFilename: false,
+            type: "application/octet-stream"
         });
         if (abortController.signal.aborted) throw new UploadCanceledError();
 

test/ContentMessages-test.ts

@@ -312,6 +312,7 @@ describe("uploadFile", () => {
             expect.objectContaining({
                 progressHandler,
                 includeFilename: false,
+                type: "application/octet-stream"
             }),
         );
         expect(mocked(client.uploadContent).mock.calls[0][0]).not.toBe(file);