test: Roughly convert test/config-files.spec.js to typescript

Author: TimothyJones

defaults.ts

@@ -1,5 +1,5 @@
 import spec from "conventional-changelog-config-spec/versions/2.1.0/schema.json";
-import { PrettyPrint } from "type-helpers";
+import { PrettyPrint } from "./type-helpers";
 
 const defaults = {
   infile: "CHANGELOG.md",

lib/opts/index.ts

@@ -113,5 +113,9 @@ export const getMergedConfig = async (
   });
 
   const configFromFile = await getConfigFromFile();
-  return { ...(legacyConf ?? {}), ...(modernConf ?? {}), ...(configFromFile ?? {}) };
+  return {
+    ...(legacyConf ?? {}),
+    ...(modernConf ?? {}),
+    ...(configFromFile ?? {}),
+  };
 };