chore(deps): remove button-group from package-lock

package-lock.json

@@ -40,16 +40,6 @@
         "styled-components": "1.3.0"
       }
     },
-    "@atlaskit/button-group": {
-      "version": "1.5.3",
-      "resolved": "https://registry.npmjs.org/@atlaskit/button-group/-/button-group-1.5.3.tgz",
-      "integrity": "sha1-Z1TmEtDQ1QdZvMzl2rhFblyPS6Q=",
-      "requires": {
-        "@atlaskit/util-shared-styles": "2.10.4",
-        "prop-types": "15.6.0",
-        "styled-components": "1.3.0"
-      }
-    },
     "@atlaskit/dropdown-menu": {
       "version": "3.10.2",
       "resolved": "https://registry.npmjs.org/@atlaskit/dropdown-menu/-/dropdown-menu-3.10.2.tgz",