(chore) Update lockfile

Author: AllenBW

yarn.lock

@@ -8205,9 +8205,9 @@ webpack-sources@^1.0.1:
     source-list-map "^2.0.0"
     source-map "~0.5.3"
 
-[email protected].0:
-  version "3.9.0"
-  resolved "https://registry.yarnpkg.com/webpack/-/webpack-3.9.0.tgz#7d65ca4ba92ae1b67be2c00b217fb990b8ffa97f"
+[email protected].1:
+  version "3.9.1"
+  resolved "https://registry.yarnpkg.com/webpack/-/webpack-3.9.1.tgz#9a60aa544ed5d4d454c069e3f521aa007e02643c"
   dependencies:
     acorn "^5.0.0"
     acorn-dynamic-import "^2.0.0"