don't always re-run effect

src/webex/pages/pay.tsx

@@ -53,7 +53,7 @@ function TalerPayDialog({ talerPayUri }: { talerPayUri: string }) {
       setPayStatus(p);
     };
     doFetch();
-  });
+  }, [numTries]);
 
   if (!payStatus) {
     return <span>Loading payment information ...</span>;

src/webex/pages/refund.tsx

@@ -49,7 +49,7 @@ function RefundStatusView(props: { talerRefundUri: string }) {
       }
     };
     doFetch();
-  });
+  }, []);
 
   console.log("rendering");