build: skip typechecking app-plaid.js

Doesn't appear to be used; there isn't any plaid depedency in the
package file.

tsconfig.json

@@ -16,5 +16,5 @@
     "moduleResolution": "Node",
     "module": "ESNext"
   },
-  "exclude": ["node_modules", "build"]
+  "exclude": ["node_modules", "build", "./app-plaid.js"]
 }