Repro #38354 - Not able to switch between databases after a question is created (#38387)

* Add e2e test for metabase#38354

* Rename file to match issue id

* Tag the test as external since it uses QA DBs

* Fix ORDERS_ID

e2e/test/scenarios/question/reproductions/38354-changing-source-database.cy.spec.js

+import {
+  getNotebookStep,
+  openNotebook,
+  popover,
+  restore,
+  visualize,
+} from "e2e/support/helpers";
+import { SAMPLE_DATABASE } from "e2e/support/cypress_sample_database";
+
+const { ORDERS_ID } = SAMPLE_DATABASE;
+
+const QUESTION_DETAILS = {
+  query: {
+    "source-table": ORDERS_ID,
+    limit: 5,
+  },
+};
+
+describe("issue 38354", { tags: "@external" }, () => {
+  beforeEach(() => {
+    restore();
+    restore("postgres-12");
+    cy.signInAsAdmin();
+    cy.createQuestion(QUESTION_DETAILS, { visitQuestion: true });
+  });
+
+  it("should be possible to change source database (metabase#38354)", () => {
+    openNotebook();
+    getNotebookStep("data").findByTestId("data-step-cell").click();
+    popover().within(() => {
+      cy.icon("chevronleft").click();
+      cy.findByText("QA Postgres12").click();
+      cy.findByText("Orders").click();
+    });
+
+    // optimization: add a limit so that query runs faster
+    cy.button("Row limit").click();
+    getNotebookStep("limit").findByPlaceholderText("Enter a limit").type("5");
+
+    visualize();
+
+    cy.findByTestId("query-builder-main")
+      .findByText("There was a problem with your question")
+      .should("not.exist");
+    cy.get(".cellData").should("contain", "37.65"); // assert visualization renders the data
+  });
+});