deps: bump victron-mqtt from 2026.5.2 to 2026.5.4 (#400)

Bumps [victron-mqtt](https://github.com/tomer-w/victron_mqtt) from 2026.5.2 to 2026.5.4.
- [Release notes](https://github.com/tomer-w/victron_mqtt/releases)
- [Changelog](https://github.com/tomer-w/victron_mqtt/blob/main/CHANGELOG.md)
- [Commits](tomer-w/victron_mqtt@v2026.5.2...v2026.5.4)

---
updated-dependencies:
- dependency-name: victron-mqtt
  dependency-version: 2026.5.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

requirements.txt

@@ -3,4 +3,4 @@ pytest-asyncio
 pytest_homeassistant_custom_component
 syrupy
 homeassistant
-victron-mqtt==2026.5.2
+victron-mqtt==2026.5.4