Remove reference of createEntry

[ashryanbeats]

Submit an issue

Topic

This is an issue regarding:

• [x] The tutorials contained within this repo.
• [ ] The samples contained within this repo.

https://github.com/AdobeXD/plugin-docs/blob/master/reference/uxp/storage-index.md

Description of the issue

createEntry isn't documented in the references and should be removed from the storage overview linked above.

Proposed solution or attempted solutions that failed

Switch it out for createFile.