build!: rm targets, add .browserslistrc (#1003)

BREAKING CHANGE: `targets` are no longer set for `@babel/preset-env`.

In this commit, we introduced a breaking change in the way that browser
`targets` work, namely in that the targets are no longer set and the
user is expected to provide their own `.browserslistrc` or similar
configuration.

The previous behavior was to have browser `targets`, which overrides any
other configuration, including `.browserslistrc`.

From the `@babel/preset-env` documentation[^1]:
> By default `@babel/preset-env` will use browserslist config sources
> unless either the `targets` or `ignoreBrowserslistConfig` options are
> set.

When upgrading to the next major version that includes this change, *you
must provide your own configuration* or else Babel will default to using
the oldest browsers available[^2].

1. https://babeljs.io/docs/en/babel-preset-env#browserslist-integration
2. https://babeljs.io/docs/en/options#no-targets

packages/babel-preset-kyt-core/src/__tests__/__snapshots__/index.test.js.snap

@@ -37,13 +37,6 @@ Object {
         "corejs": "3.18.0",
         "forceAllTransforms": true,
         "modules": "commonjs",
-        "targets": Object {
-          "browsers": Array [
-            ">1%",
-            "last 4 versions",
-            "not ie < 11",
-          ],
-        },
         "useBuiltIns": "entry",
       },
     ],

packages/babel-preset-kyt-core/src/index.js

@@ -14,9 +14,6 @@ module.exports = function getPresetCore(context, opts) {
     useBuiltIns: 'entry',
     corejs: pkg.dependencies['core-js'],
     forceAllTransforms: true,
-    targets: {
-      browsers: ['>1%', 'last 4 versions', 'not ie < 11'],
-    },
   };
 
   const serverEnvOptions = {

packages/kyt-starter-static/starter-src/.browserslistrc

@@ -0,0 +1,12 @@
+# Browsers that we support
+
+>1%
+last 4 versions
+not ie > 0
+not bb > 0
+not ie_mob > 0
+not opera > 0
+not kaios > 0
+not op_mob > 0
+not op_mini all
+not baidu > 0

packages/kyt-starter-universal/starter-src/.browserslistrc

@@ -0,0 +1,12 @@
+# Browsers that we support
+
+>1%
+last 4 versions
+not ie > 0
+not bb > 0
+not ie_mob > 0
+not opera > 0
+not kaios > 0
+not op_mob > 0
+not op_mini all
+not baidu > 0