Set up unit tests that works with staking ts lib

[supertong]

The main problem of those import complains are caused by the testEnvironment setup in Jest config.

When we set testEnvironment: jsdom, the jest default resolver would assume it's in browser environment which means it will consume the browser condition from the exports. For example, the @bitcoin-js/tiny-secp256k1-asmjs has the following exports field

  "exports": {
    ".": {
      "node": {
        "module": "./lib/index.js",
        "require": "./lib/cjs/index.cjs",
        "import": "./lib/index.js"
      },
      "browser": "./lib/index.js",
      "default": "./lib/index.js"
    }
  },

The Jest resolver will pick up "browser": "./lib/index.js", however what we want is the cjs version for the test.

We had tried a few fix and it didn't quite work and these fixes includes

• Transpile the library by specifying transformIgnorePatterns. For some reason the compiled code complains about invalid library error.

• A custom jest resolver.

  const modulesToLoadFromNodeExports = ['@bitcoin-js/tiny-secp256k1-asmjs'] 
  module.exports = (path, options) => {
  if (modulesToLoadFromNodeExports.some(module => path.includes(module))) {
  return options.defaultResolver(path, { ...options, conditions: ["node", "require"] });
  }
  
  return options.defaultResolver(path, options);
  };

  This ends with with the same error as the above.

• The working solution seems to be overwriting the testEnvironment for that specify test file with comment

  /**
  * @jest-environment node
  */

I have also updated jest configs to use the one from next/jest to simplify things a bit.

Also, the CI build requires the PR https://github.com/babylonchain/btc-staking-ts/pull/27 to be released into NPM and bump the package.

[jrwbabylonlab]

@supertong i added below in the jest config to get away with the node annotation in each ts file

projects: [
    {
      displayName: "node",
      testEnvironment: "node",
      testMatch: ["<rootDir>/tests/**/*.test.ts"],
    },
    {
      displayName: "jsdom",
      testEnvironment: "jsdom",
      testMatch: ["<rootDir>/tests/**/*.test.tsx"],
    },
  ],

[jrwbabylonlab]

@gbarkhatov and @jeremy-babylonchain i will let u guys review this as i heavily involved in making of this PR. there is no point for me to approve commits from myself