Jest transform workaround for ESM-only packages

Enables Babel transform for ESM-only packages (to CommonJS) until Jest supports ESM https://jestjs.io/docs/ecmascript-modules

jest.config.js

@@ -9,7 +9,26 @@ const config = {
   testEnvironment: './config/jest/environment/node.mjs',
   transform: {
     '^.+\\.m?js$': ['babel-jest', { rootMode: 'upward' }]
-  }
+  },
+
+  // Enable Babel transform for ESM-only packages to CommonJS
+  // until Jest supports ESM https://jestjs.io/docs/ecmascript-modules
+  transformIgnorePatterns: [
+    `/node_modules/?!(${[
+      'del',
+      'slash',
+
+      // Including child dependencies
+      'aggregate-error',
+      'clean-stack',
+      'escape-string-regexp',
+      'globby',
+      'indent-string',
+      'is-path-cwd',
+      'is-path-inside',
+      'p-map'
+    ].join('|')})`
+  ]
 }
 
 module.exports = {