Adds new integration [randomletters/motion_dimmer]

[randomletters]

Checklist

• [x] I've read the publishing documentation.
• [x] I've added the HACS action to my repository.
• [x] (For integrations only) I've added the hassfest action to my repository.
• [x] The actions are passing without any disabled checks in my repository.
• [x] I've added a link to the action run on my repository below in the links section.
• [x] I've created a new release of the repository after the validation actions were run successfully.

Links

Link to current release: https://github.com/randomletters/motion_dimmer/releases/tag/2024.5.4 Link to successful HACS action (without the ignore key): https://github.com/randomletters/motion_dimmer/actions/runs/8973877127/job/24644989850 Link to successful hassfest action (if integration): https://github.com/randomletters/motion_dimmer/actions/runs/8973877122/job/24644989877