Convert to typescript

jest.config.js

@@ -1,3 +1,11 @@
-process.env = Object.assign(process.env, {
-  GITHUB_WORKSPACE: __dirname
-});
+module.exports = {
+  clearMocks: true,
+  moduleFileExtensions: ['js', 'ts'],
+  testEnvironment: 'node',
+  testMatch: ['**/*.test.ts'],
+  testRunner: 'jest-circus/runner',
+  transform: {
+    '^.+\\.ts$': 'ts-jest'
+  },
+  verbose: true
+}