plugins: remove usages of --experimental-type-build

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

plugins/user-settings-backend/package.json

@@ -9,10 +9,22 @@
     "role": "backend-plugin"
   },
   "publishConfig": {
-    "access": "public",
-    "main": "dist/index.cjs.js",
-    "types": "dist/index.d.ts",
-    "alphaTypes": "dist/index.alpha.d.ts"
+    "access": "public"
+  },
+  "exports": {
+    ".": "./src/index.ts",
+    "./alpha": "./src/alpha.ts",
+    "./package.json": "./package.json"
+  },
+  "typesVersions": {
+    "*": {
+      "alpha": [
+        "src/alpha.ts"
+      ],
+      "package.json": [
+        "package.json"
+      ]
+    }
   },
   "homepage": "https://backstage.io",
   "repository": {
@@ -22,7 +34,7 @@
   },
   "scripts": {
     "start": "backstage-cli package start",
-    "build": "backstage-cli package build --experimental-type-build",
+    "build": "backstage-cli package build",
     "lint": "backstage-cli package lint",
     "test": "backstage-cli package test",
     "prepack": "backstage-cli package prepack",