Replace no longer set google-green/google-red

[balloob]

Checklist

• I have updated to the latest available Home Assistant version.
• I have cleared the cache of my browser.
• I have tried a different browser to see if it is related to my browser.

The problem

When we swapped out paper-spinner for mwc in #6205, we also dropped setting four style variables that we kept around to style the spinner:

--google-red-500: #db4437;
--google-blue-500: #4285f4;
--google-green-500: #0f9d58;
--google-yellow-500: #f4b400;

The green and the red ones were actually quite widely used. We should introduce our own variables and find/replace the old references. And we should make sure the new variables will use google-red / google-green if they are defined first, to make it backwards compatible with existing themes.

Update: We actually already have error-color. We should use that one everywhere instead of google-red.

Expected behavior

Steps to reproduce

Environment

• Home Assistant release with the issue:
• Last working Home Assistant release (if known):
• Browser and browser version:
• Operating system:

State of relevant entities

Problem-relevant configuration

Javascript errors shown in your browser console/inspector

Additional information

[balloob]

Idea from @thomasloven:

We should probably have like ok-color, warning-color and info-color too.

[balloob]

Note, bootstrap uses success-color instead of ok-color, which I like more

[thomasloven]

I was thinking of bootstrap when I suggested it, but was too lazy to look up the names...