Synapse Studio (browser-based interface) is not the best place to execute a long running query. You know ... you close the browser by mistake and the query aborts. Deferred compute options are preferred here. For instance, having a Synapse Pipeline and run the stored procedure from it would do the trick, with a few cents of a US dollar cost added to it.
With that said, I am not aware of any setting in the studio itself for query timeout. @Prabhat Rawat , I would recommend using either SSMS or ADS.