ci: add back old babel-preset

tried to use babel-jest and latest rc version of babel but couldn't make it work. Don't want to
spend more time on this for the moment

Author: posva

.babelrc

@@ -0,0 +1,12 @@
+{
+  "presets": [
+    [
+      "env",
+      {
+        "targets": {
+          "browsers": ["last 2 Chrome versions"]
+        }
+      }
+    ]
+  ]
+}

packages/@posva/vuefire-core/package.json

@@ -34,6 +34,7 @@
   "devDependencies": {
     "@posva/vuefire-test-helpers": "^1.0.0",
     "@types/jest": "^23.3.1",
+    "babel-preset-env": "^1.7.0",
     "eslint": "^5.3.0",
     "eslint-plugin-vue-libs": "^3.0.0",
     "firebase": "^5.3.1",

packages/vuefire/package.json

@@ -54,6 +54,7 @@
   "devDependencies": {
     "@posva/vuefire-bundler": "^1.0.0",
     "@posva/vuefire-test-helpers": "^1.0.0",
+    "babel-preset-env": "^1.7.0",
     "eslint": "^5.3.0",
     "eslint-plugin-vue-libs": "^3.0.0",
     "jest": "^23.5.0",

packages/vuexfire/package.json

@@ -56,6 +56,7 @@
   "devDependencies": {
     "@posva/vuefire-bundler": "^1.0.0",
     "@posva/vuefire-test-helpers": "^1.0.0",
+    "babel-preset-env": "^1.7.0",
     "codecov": "^3.0.1",
     "eslint": "^5.3.0",
     "eslint-plugin-vue-libs": "^3.0.0",