Fix MQTT Light Breaking Change details header

[TomBrien]

Proposed change

The breaking change for MQTT Light was listed under a duplicate SolarEdge header. Fixed that and change the MQTT above to MQTT Fan for clarity.

Side question: Should the doc links for the two MQTT breaking changes go to the relative integrations (fan and light) instead of the top level MQTT docs?

Type of change

• Spelling, grammar or other readability improvements (current branch).
• Adjusted missing or incorrect information in the current documentation (current branch).
• Added documentation for a new integration I'm adding to Home Assistant (next branch).
  • I've opened up a PR to add logo's and icons in Brands repository.
• Added documentation for a new feature I'm adding to Home Assistant (next branch).
• Removed stale or deprecated documentation.

Additional information

• Link to parent pull request in the codebase:
• Link to parent pull request in the Brands repository:
• This PR fixes or closes issue:

Checklist

• This PR uses the correct branch, based on one of the following:
  • I made a change to the existing documentation and used the current branch.
  • I made a change that is related to an upcoming version of Home Assistant and used the next branch.
• The documentation follows the Home Assistant documentation standards.

[frenck]

Thanks, @TomBrien 👍