chore(deps-dev): bump prettier from 1.15.2 to 1.19.1 (#307)

Bumps [prettier](https://github.com/prettier/prettier) from 1.15.2 to 1.19.1.
- [Release notes](https://github.com/prettier/prettier/releases)
- [Changelog](https://github.com/prettier/prettier/blob/master/CHANGELOG.md)
- [Commits](prettier/prettier@1.15.2...1.19.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

package.json

@@ -37,7 +37,7 @@
     "@types/prettier": "1.13.2",
     "codecov": "3.6.5",
     "nyc": "11.9.0",
-    "prettier": "1.15.2",
+    "prettier": "1.19.1",
     "prettier-config-ikatyang": "1.1.1",
     "standard-version": "4.4.0",
     "tslint": "5.11.0",

yarn.lock

@@ -1891,9 +1891,9 @@ prettier-config-ikatyang@1.1.1:
   version "1.1.1"
   resolved "https://registry.yarnpkg.com/prettier-config-ikatyang/-/prettier-config-ikatyang-1.1.1.tgz#9ccab4bc2d441e4c68b58dbe8f1a4e18213c3f2d"
 
-prettier@1.15.2:
-  version "1.15.2"
-  resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.15.2.tgz#d31abe22afa4351efa14c7f8b94b58bb7452205e"
+prettier@1.19.1:
+  version "1.19.1"
+  resolved "https://registry.yarnpkg.com/prettier/-/prettier-1.19.1.tgz#f7d7f5ff8a9cd872a7be4ca142095956a60797cb"
 
 process-nextick-args@~2.0.0:
   version "2.0.0"