version key in the manifest file

[oleandor]

https://www.home-assistant.io/blog/2021/06/02/release-20216/#breaking-changes

Custom integrations (custom_components)
As mentioned in every release since 2021.3, custom integrations will require a version key in their manifest file.

As of this release, if that version key is missing in the manifest, the custom integration will no longer be loaded.

For more details see our developer blog about it

(@ludeeus - #49916)

https://developers.home-assistant.io/blog/2021/01/29/custom-integration-changes/#versions