fix: Server error when rendering share for deleted document

closes #2352

server/app.test.js

@@ -28,6 +28,19 @@ describe("/share/:id", () => {
     expect(body).toContain("<title>Outline</title>");
   });
 
+  it("should return standard title in html when document is deleted", async () => {
+    const document = await buildDocument();
+    const share = await buildShare({ documentId: document.id });
+
+    await document.destroy();
+
+    const res = await server.get(`/share/${share.id}`);
+    const body = await res.text();
+
+    expect(res.status).toEqual(200);
+    expect(body).toContain("<title>Outline</title>");
+  });
+
   it("should return document title in html when loading published share", async () => {
     const document = await buildDocument();
     const share = await buildShare({ documentId: document.id });