Improve test coverage

src/__snapshots__/AppBar.test.tsx.snap

@@ -42,3 +42,56 @@ exports[`AppBar > renders 1`] = `
   </p>
 </div>
 `;
+
+exports[`AppBar > renders with title and subtitle 1`] = `
+<div>
+  <div
+    class="bar"
+  >
+    <header>
+      <button
+        aria-labelledby="_r_6_"
+        class="_icon-button_1215g_8 primaryButton"
+        data-kind="primary"
+        role="button"
+        style="--cpd-icon-button-size: 24px;"
+        tabindex="0"
+      >
+        <div
+          class="_indicator-icon_147l5_17"
+          style="--cpd-icon-button-size: 100%;"
+        >
+          <svg
+            aria-hidden="true"
+            fill="currentColor"
+            height="1em"
+            viewBox="0 0 24 24"
+            width="1em"
+            xmlns="http://www.w3.org/2000/svg"
+          >
+            <path
+              d="M12 11.034a1 1 0 0 0 .29.702l.005.005c.18.18.43.29.705.29h8a1 1 0 0 0 0-2h-5.586L22 3.445a1 1 0 0 0-1.414-1.414L14 8.617V3.031a1 1 0 1 0-2 0zm0 1.963a1 1 0 0 0-.29-.702l-.005-.004A1 1 0 0 0 11 12H3a1 1 0 1 0 0 2h5.586L2 20.586A1 1 0 1 0 3.414 22L10 15.414V21a1 1 0 0 0 2 0z"
+            />
+          </svg>
+        </div>
+      </button>
+      <h1
+        class="_typography_6v6n8_153 _font-body-lg-medium_6v6n8_79 title"
+      >
+        Title
+      </h1>
+      <span
+        class="_typography_6v6n8_153 _font-body-lg-regular_6v6n8_69 subtitle"
+      >
+        Subtitle
+      </span>
+      <div
+        class="secondaryButton"
+      />
+    </header>
+  </div>
+  <p>
+    This is the content.
+  </p>
+</div>
+`;