Wrap konfig load from scripts tests to avoid changing CWD (#4067)

* chore: add utility method to get konfig from scripts tests

Local scripts specs should be be caught by the changing current
directory when loading `konfig.coffee` (which loads `cwd.coffee`,
which changes the cwd to `packages/server`). This was throwing
snapshot tests into saving into a wrong folder until I have noticed
this and fixed in
[v8.0.3](https://github.com/bahmutov/snap-shot-core/releases/tag/v8.0.3)

* linting

* add more comments

scripts/binary/get-config.js

@@ -0,0 +1,22 @@
+/**
+ * Safer konfig load for test code. The original konfig changes the
+ * current working directory, thus the tests might be affected
+ * unexpectedly. This function loads the konfig, but then
+ * restores the current working directory.
+ *
+ * The tests should use this function to get `konfig` function like
+ *
+ * @example
+ *    const konfig = require('../binary/get-config')()
+ */
+const getConfig = () => {
+  const cwd = process.cwd()
+  const konfig = require('../../packages/server/lib/konfig')
+
+  // restore previous cwd in case it was changed by loading "konfig"
+  process.chdir(cwd)
+
+  return konfig
+}
+
+module.exports = getConfig