feat(medusa-plugin-mailchimp): Migrate to TS + add update endpoint (#4040)

* - Refactored the .js files to .ts files
- Added typing
- Used 'WrapHandler' util instead of specific middleware in plugin
- Added additional PUT method to the /mailchimp/subscribe endpoint.
- Updated documentation where relevant.

* Added changeset

* Updated yarn.lock

* Used camelcase for method args in services/mailchimp.ts

---------

Co-authored-by: Tom Rupke <tom@adapptive.nl>
Co-authored-by: Oliver Windall Juhl <59018053+olivermrbl@users.noreply.github.com>

packages/medusa-plugin-mailchimp/package.json

@@ -8,34 +8,26 @@
     "url": "https://github.com/medusajs/medusa",
     "directory": "packages/medusa-plugin-mailchimp"
   },
-  "author": "Oliver Juhl",
+  "author": "Oliver Juhl, Tomek Pur",
   "license": "MIT",
   "devDependencies": {
-    "@babel/cli": "^7.7.5",
-    "@babel/core": "^7.7.5",
-    "@babel/node": "^7.7.4",
-    "@babel/plugin-proposal-class-properties": "^7.7.4",
-    "@babel/plugin-transform-instanceof": "^7.8.3",
-    "@babel/plugin-transform-runtime": "^7.7.6",
-    "@babel/preset-env": "^7.7.5",
-    "@babel/register": "^7.7.4",
-    "@babel/runtime": "^7.9.6",
+    "@medusajs/medusa": "1.10.0",
+    "@types/express": "^4.17.17",
     "client-sessions": "^0.8.0",
     "cross-env": "^5.2.1",
     "jest": "^25.5.4",
-    "medusa-interfaces": "^1.3.7"
+    "typescript": "^4.4.4"
   },
   "scripts": {
     "prepare": "cross-env NODE_ENV=production yarn run build",
     "test": "jest --passWithNoTests src",
-    "build": "babel src --out-dir . --ignore '**/__tests__','**/__mocks__'",
-    "watch": "babel -w src --out-dir . --ignore '**/__tests__','**/__mocks__'"
+    "build": "tsc",
+    "watch": "tsc --watch"
   },
   "peerDependencies": {
-    "medusa-interfaces": "1.3.7"
+    "@medusajs/medusa": "1.10.0"
   },
   "dependencies": {
-    "@babel/plugin-transform-classes": "^7.9.5",
     "body-parser": "^1.19.0",
     "cors": "^2.8.5",
     "express": "^4.17.1",