add backtage config package to deps

Signed-off-by: Emma Indal <emma.indahl@gmail.com>
Signed-off-by: Eric Peterson <ericpeterson@spotify.com>

plugins/search/package.json

@@ -33,6 +33,7 @@
     "@backstage/catalog-model": "^0.8.0",
     "@backstage/plugin-catalog-react": "^0.2.0",
     "@backstage/search-common": "^0.1.1",
+    "@backstage/config": "^0.1.5",
     "@backstage/theme": "^0.2.8",
     "@material-ui/core": "^4.11.0",
     "@material-ui/icons": "^4.9.1",