Adjust / theme entity marker background color

[spacegaier]

Breaking change

Proposed change

Previously the entity marker color was hardcoded to white. Now it is following the theme variables (same one that is used in the sidebar for the user avatar if no image is uploaded). Makes the markers less jarring in the dark theme (previously white on dark gray map) and stand out more in the light theme (white on white map).

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 #
• This PR is related to issue or discussion:
• Link to documentation pull request:

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

[spacegaier]

Removed since can never take effect due to display: block;