Above answers did not work for me exactly. I use rails 8. Instead of EDITOR I used VISUAL keyword.

VISUAL="/opt/homebrew/bin/vim" bin/rails credentials:edit

You can see it is written on help:

bin/rails credentials:help

Editing Credentials: bin/rails credentials:edit will open a temporary file in $VISUAL or $EDITOR with the decrypted contents to edit the encrypted credentials.

When the temporary file is next saved the contents are encrypted and written to
`config/credentials.yml.enc` while the file itself is destroyed to prevent credentials
from leaking.