chore(package): update lockfile yarn.lock

Author: greenkeeper[bot]

yarn.lock

@@ -5975,10 +5975,10 @@ webpack-sources@^1.3.0:
     source-list-map "^2.0.0"
     source-map "~0.6.1"
 
-webpack@^4.26.1:
-  version "4.26.1"
-  resolved "https://registry.yarnpkg.com/webpack/-/webpack-4.26.1.tgz#ff3a9283d363c07b3494dfa702d08f4f2ef6cb39"
-  integrity sha512-i2oOvEvuvLLSuSCkdVrknaxAhtUZ9g+nLSoHCWV0gDzqGX2DXaCrMmMUpbRsTSSLrUqAI56PoEiyMUZIZ1msug==
+webpack@^4.28.0:
+  version "4.28.0"
+  resolved "https://registry.yarnpkg.com/webpack/-/webpack-4.28.0.tgz#6bdc26c17fe4c7e28c29fa002e6d37ac92caae9e"
+  integrity sha512-gPNTMGR5ZlBucXmEQ34TRxRqXnGYq9P3t8LeP9rvhkNnr+Cn+HvZMxGuJ4Hl7zdmoRUZP+GosniqJiadXW/RqQ==
   dependencies:
     "@webassemblyjs/ast" "1.7.11"
     "@webassemblyjs/helper-module-context" "1.7.11"