Add "show_names" option to history graphs

[spacegaier]

Breaking change

Proposed change

Add the optional parameter "show_names" to history graph card to hide the names. This solves the use cases described in the linked issue. At the same time I removed the confusing "no-single" / "isSingleDevice" logic for a cleaner "showNames" approach. There was no longer any usage where looking at the amount of timelines to determine what to show made sense since via "no-single" usage that was anyway practically disabled.

The timeline in the more-info of course still hides the timeline name since here it is clear from the context what is shown (similar to the use cases described in the linked issue).

The default is still that names are always shown, so this is not a breaking change.

Note: Doc update will follow once we are aligned that we will merge in this new option.

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New feature (thank you!)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Example configuration

Additional information

• This PR fixes or closes issue: fixes history-graph: do not show a name if only ONE graph is displayed (like it was before 2022.6.1) #12860
• This PR is related to issue or discussion:
• Link to documentation pull request: History graph card: Add new option "show_names" home-assistant.io#25157

Checklist

• The code change is tested and works locally.
• There is no commented out code in this PR.
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io