Tests

Raise warning if both c and facecolors are used in scatter plot (... and related improvements in the test suite). #26065

Job	Run time
Python 3.10 on ubuntu-20.04 (Minimum Versions)	20m 4s
Python 3.10 on ubuntu-20.04	18m 9s
Python 3.11 on ubuntu-22.04	18m 21s
Python 3.12 on ubuntu-22.04	21m 31s
Python 3.13 on ubuntu-22.04	20m 58s
Python 3.13t on ubuntu-22.04 Free-threaded	18m 40s
Python 3.10 on macos-13	26m 49s
Python 3.12 on macos-14	18m 22s
Python 3.13 on macos-14	17m 14s
Create issue on failure	0s
	3h 0m 8s

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