Operation Location getting null

` ReadHeaders responseHeader = vision.readWithServiceResponseAsync(remoteTextImageURL, null, null,null)
.toBlocking()
.single()
.headers();
String operationLocation = responseHeader.operationLocation();`

here it is retrieving null as operation location, could you help me to resolve this issue.

Locate the Java quickstart containing the shown `vision.readWithServiceResponseAsync` call and inspect how the response headers are handled. Reproduce the request with the supplied arguments, verify the returned operation response and SDK behavior, and confirm the operation location is available or document the required correction.

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