Update dependency rollup to v1.21.1

Author: renovate-bot

package.json

@@ -17,7 +17,7 @@
   },
   "devDependencies": {
     "prettier": "1.16.4",
-    "rollup": "1.20.3",
+    "rollup": "1.21.1",
     "rollup-plugin-node-resolve": "4.0.1"
   }
 }

yarn.lock

@@ -7,10 +7,10 @@
   resolved "https://registry.yarnpkg.com/@types/estree/-/estree-0.0.39.tgz#e177e699ee1b8c22d23174caaa7422644389509f"
   integrity sha512-EYNwp3bU+98cpU4lAWYYL7Zz+2gryWH1qbdDTidVd6hkiR6weksdbMadyXKXNPEkQFhXM+hVO9ZygomHXp+AIw==
 
-"@types/node@^12.7.2":
-  version "12.7.2"
-  resolved "https://registry.yarnpkg.com/@types/node/-/node-12.7.2.tgz#c4e63af5e8823ce9cc3f0b34f7b998c2171f0c44"
-  integrity sha512-dyYO+f6ihZEtNPDcWNR1fkoTDf3zAK3lAABDze3mz6POyIercH0lEUawUFXlG8xaQZmm1yEBON/4TsYv/laDYg==
+"@types/node@^12.7.4":
+  version "12.7.4"
+  resolved "https://registry.yarnpkg.com/@types/node/-/node-12.7.4.tgz#64db61e0359eb5a8d99b55e05c729f130a678b04"
+  integrity sha512-W0+n1Y+gK/8G2P/piTkBBN38Qc5Q1ZSO6B5H3QmPCUewaiXOo2GCAWZ4ElZCcNhjJuBSUSLGFUJnmlCn5+nxOQ==
 
 "@vaadin/[email protected]":
   version "1.4.1"
@@ -83,11 +83,11 @@ [email protected]:
     is-module "^1.0.0"
     resolve "^1.10.0"
 
-rollup@1.20.3:
-  version "1.20.3"
-  resolved "https://registry.yarnpkg.com/rollup/-/rollup-1.20.3.tgz#6243f6c118ca05f56b2d9433112400cd834a1eb8"
-  integrity sha512-/OMCkY0c6E8tleeVm4vQVDz24CkVgvueK3r8zTYu2AQNpjrcaPwO9hE+pWj5LTFrvvkaxt4MYIp2zha4y0lRvg==
+rollup@1.21.1:
+  version "1.21.1"
+  resolved "https://registry.yarnpkg.com/rollup/-/rollup-1.21.1.tgz#b27a19b2bd0b3712bdfc76ef7357d915e1860c82"
+  integrity sha512-gM1EK/TsXES5xPYk7YG8VxM160DKMs2zSpSD3TBR1pdqYn/uKK85lJrsTIVXEYORR4xxzJdHzphkMFHRGNRxsw==
   dependencies:
     "@types/estree" "0.0.39"
-    "@types/node" "^12.7.2"
+    "@types/node" "^12.7.4"
     acorn "^7.0.0"