Use different equality tester of scales

[teunbrand]

Hello there,

We have been preparing a new release of ggplot2 and during a reverse dependency check, it became apparent that the prospective ggplot2 3.5.0 would break tvthemes.

We changed the internals of scales a bit to provide more accurate error messages. Unfortunately, this makes testing for the equality of scales a bit more difficult. This PR updates the tests to ignore the call field of scales. In addition, a few tests for the scale_name field were deleted, as this field is to become deprecated in the new ggplot2 version.

To test the code changes with the release candidate, you can install it with the code below:

remotes::install_github("tidyverse/ggplot2", ref = remotes::github_pull("5592"))

The release of ggplot2 3.5.0 is scheduled for the 12th of February. The progress of the release can be tracked in tidyverse/ggplot2#5588. We hope that this PR might help tvthemes get out a fix if necessary.

[teunbrand]

This is just a kind reminder that the release of ggplot2 is scheduled soon.

[Ryo-N7]

thanks, done!