Remove quotation marks from object key (#68337)
## For Contributors
### Improving Documentation
- [x] Run `pnpm prettier-fix` to fix formatting issues before opening
the PR.
- [x] Read the Docs Contribution Guide to ensure your contribution
follows the docs guidelines:
https://nextjs.org/docs/community/contribution-guide
### What?
In the example given in the types declaration file, the key `images` is
wrapped in quotation marks. I removed the quotation marks.
### Why?
The quotation marks are inconsistent with the other examples, which do
not use quotes for Object key names.
### How?
N/A
Co-authored-by: Jiwon Choi <devjiwonchoi@gmail.com>
