Update execa to the latest version 🚀 (#56)

[skip ci] fix(package): update execa to version 1.0.0

* chore(package): update lockfile

https://npm.im/greenkeeper-lockfile

package.json

@@ -29,7 +29,7 @@
   "private": false,
   "dependencies": {
     "electron-builder": "^20.28.1",
-    "execa": "^0.11.0",
+    "execa": "^1.0.0",
     "fs-extra": "^7.0.0",
     "lodash.merge": "^4.6.1",
     "portfinder": "^1.0.16",

yarn.lock

@@ -4630,18 +4630,6 @@ execa@^0.10.0:
     signal-exit "^3.0.0"
     strip-eof "^1.0.0"
 
-execa@^0.11.0:
-  version "0.11.0"
-  resolved "https://registry.yarnpkg.com/execa/-/execa-0.11.0.tgz#0b3c71daf9b9159c252a863cd981af1b4410d97a"
-  dependencies:
-    cross-spawn "^6.0.0"
-    get-stream "^4.0.0"
-    is-stream "^1.1.0"
-    npm-run-path "^2.0.0"
-    p-finally "^1.0.0"
-    signal-exit "^3.0.0"
-    strip-eof "^1.0.0"
-
 execa@^0.7.0:
   version "0.7.0"
   resolved "https://registry.yarnpkg.com/execa/-/execa-0.7.0.tgz#944becd34cc41ee32a63a9faf27ad5a65fc59777"
@@ -4666,6 +4654,18 @@ execa@^0.8.0:
     signal-exit "^3.0.0"
     strip-eof "^1.0.0"
 
+execa@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/execa/-/execa-1.0.0.tgz#c6236a5bb4df6d6f15e88e7f017798216749ddd8"
+  dependencies:
+    cross-spawn "^6.0.0"
+    get-stream "^4.0.0"
+    is-stream "^1.1.0"
+    npm-run-path "^2.0.0"
+    p-finally "^1.0.0"
+    signal-exit "^3.0.0"
+    strip-eof "^1.0.0"
+
 exit@^0.1.2:
   version "0.1.2"
   resolved "https://registry.yarnpkg.com/exit/-/exit-0.1.2.tgz#0632638f8d877cc82107d30a0fff1a17cba1cd0c"