fix: 🐛 fix new TypeScript errors

Author: streamich

src/Modal/index.ts

@@ -29,6 +29,7 @@ export class Modal extends Component<IModalProps, IModalState> {
   id: number;
   el: HTMLElement = null;
   activeEl: Element; // Previous active element;
+  state;
 
   constructor (props, context) {
     super(props, context);

src/Slider/index.ts

@@ -37,6 +37,7 @@ export class Slider extends Component<ISliderProps, ISliderState> {
   CLIENT_X = 'clientX';
   el: HTMLElement = null;
   mounted = false;
+  state;
 
   constructor (props, context) {
     super(props, context);