fix(package): update execa to version 4.0.0

Author: pvdlg

package.json

@@ -23,7 +23,7 @@
     "aggregate-error": "^3.0.0",
     "debug": "^4.0.0",
     "dir-glob": "^3.0.0",
-    "execa": "^3.2.0",
+    "execa": "^4.0.0",
     "lodash": "^4.17.4",
     "micromatch": "^4.0.0",
     "p-reduce": "^2.0.0"