Fix compiling API (#5190)

- Since Typescript 4.2 some Helpers to transpile to 4.2 are deprecated/removed. This includes __spread and __spreadArrays microsoft/TypeScript#41523.
- We heavily use the spread syntax in Dark Reader and thus need those helper functions.
- Due the upgrade of 4.2, tslib was outdated and didn't had the new helper function `__spreadArray`.
- After good hours of skimming trough the compiler and using the wrong commands to update tslib(default to 1.x). manually updating it to 2.1 which includes this new functions microsoft/tslib#133
https://github.com/microsoft/tslib/releases/tag/2.1.0
the API can be properly compiled again.
- Resolves #My personal issues with the API.

Note to myself: Now their are 2 versions installed `2.1.10` and `1.14.1` properly configuration setups should default to 2.1.10. But for sakes if I get into problems with this I hope I remember this note and don't waste some hours. Why `1.14.1`, I don't know. `npm --save-dev -E tslib` defaults to 1.14.1. It seems like an NPM bug `yarn add --dev -E tslib` gives the correct 2.1.10. Damn dependency hell =).

package.json

@@ -97,6 +97,7 @@
     "ts-jest": "26.5.2",
     "ts-node": "9.1.1",
     "tsconfig-paths": "3.9.0",
+    "tslib": "2.1.0",
     "typescript": "4.2.2",
     "web-ext": "5.5.0",
     "ws": "7.4.3",