Update babel.config.js so build artifacts are compiled to ES5. (rjsf-…

…team#3304)

dts-cli will utilize the babel.config.js file on build. The `targets` option for the @babel/preset-env plugin will determine what features the compiled output will target. Per babel docs:

 > When no targets are specified: Babel will assume you are targeting the oldest browsers possible. For example, @babel/preset-env will transform all ES2015-ES2020 code to be ES5 compatible.

 This approach will allow us to continue to write ESNext code while we can be confident RJSF users will still consume ES5 code.

CHANGELOG.md

@@ -19,6 +19,7 @@ should change the heading of the (upcoming) version to include a major version b
 
 # @rjsf/core
 - Pass the `schema` along to the `ArrayFieldItemTemplate` as part of the fix for [#3253](https://github.com/rjsf-team/react-jsonschema-form/issues/3253)
+- Tweak Babel configuration to emit ES5-compatible output files, fixing [#3240](https://github.com/rjsf-team/react-jsonschema-form/issues/3240)
 
 # @rjsf/utils
 - Update the `ArrayFieldItemTemplate` to add `schema` as part of the fix for [#3253](https://github.com/rjsf-team/react-jsonschema-form/issues/3253)

babel.config.js

@@ -1,7 +1,7 @@
 const BABEL_ENV = process.env.BABEL_ENV;
 const IS_TEST = BABEL_ENV === "test"
 const ignore = IS_TEST ? [] : ['test/**/*.js']
-const targets = IS_TEST ? { node: "current" } : { browsers: "defaults" }
+const targets = IS_TEST ? { node: "current" } : {}
 
 module.exports = {
   presets: [