use classnames lib instead of duplicated styles

plugins/catalog/package.json

@@ -32,6 +32,7 @@
     "@material-ui/core": "^4.11.0",
     "@material-ui/icons": "^4.9.1",
     "@material-ui/lab": "4.0.0-alpha.45",
+    "classnames": "^2.2.6",
     "moment": "^2.26.0",
     "react": "^16.13.1",
     "react-dom": "^16.13.1",

plugins/catalog/src/components/AboutCard/IconLinkVertical/IconLinkVertical.tsx

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 import * as React from 'react';
+import classnames from 'classnames';
 import { makeStyles, Link } from '@material-ui/core';
 import LinkIcon from '@material-ui/icons/Link';
 
@@ -32,10 +33,6 @@ const useIconStyles = makeStyles({
     textAlign: 'center',
   },
   disabled: {
-    display: 'grid',
-    justifyItems: 'center',
-    gridGap: 4,
-    textAlign: 'center',
     color: 'gray',
   },
   label: {
@@ -56,7 +53,11 @@ export function IconLinkVertical({
 
   if (disabled) {
     return (
-      <Link className={classes.disabled} underline="none" {...props}>
+      <Link
+        className={classnames(classes.link, classes.disabled)}
+        underline="none"
+        {...props}
+      >
         {icon}
         <span className={classes.label}>{props.label}</span>
       </Link>