fix(demo): fix api refenrences for pager component (#4323)

Author: YevheniiaMazur

demo/src/ng-api-doc.ts

@@ -2085,7 +2085,7 @@ export const ngdoc: any = {
       {
         "name": "pageBtnClass",
         "type": "string",
-        "description": "<p>add class to <li> </p>\n"
+        "description": "<p>add class to <code>&lt;li></code> </p>\n"
       },
       {
         "name": "previousText",

src/pagination/pager.component.ts

@@ -46,7 +46,7 @@ export class PagerComponent implements ControlValueAccessor, OnInit {
   /** if true current page will in the middle of pages list */
   @Input() rotate: boolean;
   // css
-  /** add class to <li> */
+  /** add class to <code><li\></code> */
   @Input() pageBtnClass: string;
 
   /** if true pagination component will be disabled */