Fix #247. Suppress warning for spawn-sync

Author: rebornix

package.json

@@ -284,5 +284,8 @@
     "tmp": "^0.0.31",
     "vscode": "^1.1.18",
     "ws": "^6.0.0"
+  },
+  "optionalDependencies": {
+    "spawn-sync": "^2.0.0"
   }
 }

yarn.lock

@@ -5843,6 +5843,10 @@ sparkles@^1.0.0:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/sparkles/-/sparkles-1.0.1.tgz#008db65edce6c50eec0c5e228e1945061dd0437c"
 
+spawn-sync@^2.0.0:
+  version "2.0.0"
+  resolved "https://registry.yarnpkg.com/spawn-sync/-/spawn-sync-2.0.0.tgz#3af5ba4b73cc5dc8a41d3747eede71e98d949555"
+
 spdx-correct@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/spdx-correct/-/spdx-correct-3.0.0.tgz#05a5b4d7153a195bc92c3c425b69f3b2a9524c82"