remove < x.y.z engines specification (#11456)

* chore: remove lt engines specification

* remove unecessary yarn update

.travis.yml

@@ -13,7 +13,6 @@ env:
 
 install: skip
 before_script:
-  - curl -o- -L https://yarnpkg.com/install.sh | bash
   - if [ "$TRAVIS_OS_NAME" = "windows" ]; then choco install make; fi
 
 script:

package.json

@@ -75,8 +75,8 @@
     "@lerna/collect-updates": "https://github.com/babel/lerna.git#babel-collect-updates"
   },
   "engines": {
-    "node": ">= 6.9.0 < 14.0.0",
-    "npm": ">= 3.x <= 6.x",
+    "node": ">= 6.9.0",
+    "npm": ">= 3.x",
     "yarn": ">=0.27.5 || >=1.0.0-20170811"
   },
   "lint-staged": {