chore(deps-dev): bump rollup from 1.1.2 to 1.2.1

Bumps [rollup](https://github.com/rollup/rollup) from 1.1.2 to 1.2.1.
- [Release notes](https://github.com/rollup/rollup/releases)
- [Changelog](https://github.com/rollup/rollup/blob/master/CHANGELOG.md)
- [Commits](https://github.com/rollup/rollup/compare/v1.1.2...v1.2.1)

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

web3.js/package-lock.json

@@ -13898,20 +13898,20 @@
       }
     },
     "rollup": {
-      "version": "1.1.2",
-      "resolved": "https://registry.npmjs.org/rollup/-/rollup-1.1.2.tgz",
-      "integrity": "sha512-OkdMxqMl8pWoQc5D8y1cIinYQPPLV8ZkfLgCzL6SytXeNA2P7UHynEQXI9tYxuAjAMsSyvRaWnyJDLHMxq0XAg==",
+      "version": "1.2.1",
+      "resolved": "https://registry.npmjs.org/rollup/-/rollup-1.2.1.tgz",
+      "integrity": "sha512-rFf7m2MHwjSYjSCFdA7ckGluMcQRcC3dKn6uAWYrk/6wnUrdQhJJruumkk5IV/3KMdmuc9qORmTu1VPBa2Ii8w==",
       "dev": true,
       "requires": {
         "@types/estree": "0.0.39",
-        "@types/node": "9.6.6",
-        "acorn": "6.0.5"
+        "@types/node": "*",
+        "acorn": "^6.1.0"
       },
       "dependencies": {
         "acorn": {
-          "version": "6.0.5",
-          "resolved": "https://registry.npmjs.org/acorn/-/acorn-6.0.5.tgz",
-          "integrity": "sha512-i33Zgp3XWtmZBMNvCr4azvOFeWVw1Rk6p3hfi3LUDvIFraOMywb1kAtrbi+med14m4Xfpqm3zRZMT+c0FNE7kg==",
+          "version": "6.1.0",
+          "resolved": "https://registry.npmjs.org/acorn/-/acorn-6.1.0.tgz",
+          "integrity": "sha512-MW/FjM+IvU9CgBzjO3UIPCE2pyEwUsoFl+VGdczOPEdxfGFjuKny/gN54mOuX7Qxmb9Rg9MCn2oKiSUeW+pjrw==",
           "dev": true
         }
       }

web3.js/package.json

@@ -110,7 +110,7 @@
     "marked": "^0.6.0",
     "prettier": "^1.14.3",
     "rimraf": "2.6.3",
-    "rollup": "1.1.2",
+    "rollup": "1.2.1",
     "rollup-plugin-babel": "3.0.7",
     "rollup-plugin-commonjs": "9.2.0",
     "rollup-plugin-json": "^3.0.0",