Add lint to CI and fix errors (#853)

Adds lint to CI and fixes errors.
I'm not sure I'm fully proud of all the solutions there.
But there's no lint issues and the lint is being checked as part of the
CI.

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Co-authored-by: Yuri Astrakhan <yuriastrakhan@gmail.com>

src/components/_DataProperty.tsx

@@ -23,7 +23,7 @@ function setStopRefs(props: DataPropertyProps, state: DataPropertyState) {
 
   if(props.value && props.value.stops) {
     props.value.stops.forEach((_val, idx) => {
-      if(!state.refs.hasOwnProperty(idx)) {
+      if(!Object.prototype.hasOwnProperty.call(state.refs, idx)) {
         if(!newRefs) {
           newRefs = {...state};
         }
@@ -118,7 +118,7 @@ export default class DataProperty extends React.Component<DataPropertyProps, Dat
           data: stop
         }
       })
-      // Sort by zoom
+    // Sort by zoom
       .sort((a, b) => sortNumerically(a.data[0].zoom, b.data[0].zoom));
 
     // Fetch the new position of the stops