fix more type issues in unit tests (#8053)

* fix ts issues in test/components/structures

Signed-off-by: Kerry Archibald <kerrya@element.io>

* fix ts issues in test/components/views/context_menus

Signed-off-by: Kerry Archibald <kerrya@element.io>

tsconfig.json

@@ -28,5 +28,9 @@
     "./test/utils/**/*.tsx",
     "./test/stores/**/*.ts",
     "./test/stores/**/*.tsx",
+    "./test/components/structures/**/*.ts",
+    "./test/components/structures/**/*.tsx",
+    "./test/components/views/context_menus/**/*.ts",
+    "./test/components/views/context_menus/**/*.tsx",
   ],
 }