Here is how it's possible. No warranty of any kind for this code on passing the App Store review process.
if let bundle = Bundle(identifier: "com.apple.CoreGlyphs"),
let resourcePath = bundle.path(forResource: "symbol_search", ofType: "plist"),
let plist = NSDictionary(contentsOfFile: resourcePath) {
/// keys in `plist` are names of all available symbols
}