Allow WCSAxes ticklabels to be rasterized

[dstansby]

This refactors code in WCSAxes to allow ticklabels to be rasterized. This required modifying the signature of draw() so it can work with only renderer passed as an argument.

Using the example given in #12568, this improves the resulting plot from

to

Part 3/4 of #12672, and part of fixing #12568.

[github-actions]

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[dstansby]

pre-commit.ci autofix

[astrofrog]

Looks good to me, thanks!

[pllim]

Thanks!