fix(RMS test): make test less flaky by asserting the language has cha…

…nged before checking the format (#1995)

Co-authored-by: Steve Astels <[email protected]>

tests_cypress/cypress/e2e/admin/components/remaining_messages_summary.cy.js

@@ -64,6 +64,7 @@ describe("Remaining Messages Summary Component", () => {
 
     it("shows thousands separator in FR for today’s remaining", () => {
       cy.get("#header-lang").click();
+      cy.get("html").should("have.attr", "lang", "fr");
       cy.visit(PageURL);
       RMS.Below()
         .find('*[data-testid="rms"]')
@@ -82,6 +83,7 @@ describe("Remaining Messages Summary Component", () => {
 
     it("shows thousands separator in FR for the year’s remaining", () => {
       cy.get("#header-lang").click();
+      cy.get("html").should("have.attr", "lang", "fr");
       cy.visit(PageURL);
       RMS.Below()
         .find('*[data-testid="rms"]')