E2E repro 17514: another element visibility check before assert (#21199)

frontend/test/metabase/scenarios/question/reproductions/17514-ui-overlay.cy.spec.js

@@ -119,6 +119,7 @@ describe("issue 17514", () => {
       removeJoinedTable();
 
       visualize();
+      cy.findByTextEnsureVisible("Subtotal");
 
       cy.findByText("Save").click();
 
@@ -134,6 +135,7 @@ describe("issue 17514", () => {
       cy.findByText("Products").click();
 
       visualize();
+      cy.findByTextEnsureVisible("Subtotal");
 
       // Cypress cannot click elements that are blocked by an overlay so this will immediately fail if the issue is not fixed
       cy.findByText("110.93").click();