Auto merge of #116472 - matthiaskrgr:rollup-1mz0qrp, r=matthiaskrgr

Rollup of 2 pull requests

Successful merges:

 - #116421 (Clarify `invalid_reference_casting` lint around interior mutable types)
 - #116469 (Fix typo in README.md)

r? `@ghost`
`@rustbot` modify labels: rollup