Fix GET requests from graphql client when using relative url

What does this MR do?

!65564 (merged) introduced a workaround for GET requests This MR fixes this workaround when used for instances with relative url

Does this MR meet the acceptance criteria?

Conformity

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• I have self-reviewed this MR per code review guidelines.
• This MR does not harm performance, or I have asked a reviewer to help assess the performance impact. (Merge request performance guidelines)
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• This change is backwards compatible across updates, or this does not apply.

Availability and Testing

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