Fix lint issues

Author: liamness

.eslintrc.json

@@ -31,6 +31,12 @@
         "importNames": ["textSans", "headline", "titlepiece", "body"],
         "message": "Please use the modified fonts from fontNormaliser.ts"
       }
+    ],
+    "react/no-unknown-property": [
+      "error",
+      {
+        "ignore": ["css"]
+      }
     ]
   },
   "settings": {

client/src/tour/tourState.tsx

@@ -274,6 +274,7 @@ export const TourStateProvider: React.FC = ({ children }) => {
           visitTourStep(tourStepIDs[index]); // tracks in the database
           break;
         }
+        default:
       }
     }
   };