feat: Typescript for API layer (#817)

Co-authored-by: Philip Korsholm <88927411+pKorsholm@users.noreply.github.com>
Co-authored-by: Zakaria El Asri <33696020+zakariaelas@users.noreply.github.com>
Co-authored-by: Kasper Fabricius Kristensen <45367945+kasperkristensen@users.noreply.github.com>
Co-authored-by: Philip Korsholm <philip.korsholm@hotmail.com>
Co-authored-by: Sebastian Rindom <seb@medusa-commerce.com>

packages/medusa-core-utils/.babelrc

@@ -1,6 +1,6 @@
 {
   "plugins": ["@babel/plugin-proposal-class-properties"],
-  "presets": ["@babel/preset-env"],
+  "presets": ["@babel/preset-env", "@babel/preset-typescript"],
   "env": {
     "test": {
       "plugins": ["@babel/plugin-transform-runtime"]