Migrate Figure.plot3d tests to dvc

[michaelgrund]

Description of proposed changes

Related to #1131.

Reminders

• Run make format and make check to make sure the code follows the style guide.
• Add tests for new features or tests that would have caught the bug that you're fixing.
• Add new public functions/methods/classes to doc/api/index.rst.
• Write detailed docstrings for all functions/methods.
• If adding new functionality, add an example to docstrings or tutorials.

Slash Commands

You can write slash commands (/command) in the first line of a comment to perform
specific operations. Supported slash commands are:

• /format: automatically format and lint the code
• /test-gmt-dev: run full tests on the latest GMT development version

[github-actions]

Summary of changed images

This is an auto-generated report of images that have changed on the DVC remote

Status	Path
added	pygmt/tests/baseline/test_plot3d_colors.png
added	pygmt/tests/baseline/test_plot3d_colors_sizes.png
added	pygmt/tests/baseline/test_plot3d_colors_sizes_proj.png
added	pygmt/tests/baseline/test_plot3d_from_file.png
added	pygmt/tests/baseline/test_plot3d_matrix.png
added	pygmt/tests/baseline/test_plot3d_matrix_color.png
added	pygmt/tests/baseline/test_plot3d_projection.png
added	pygmt/tests/baseline/test_plot3d_red_circles_zscale.png
added	pygmt/tests/baseline/test_plot3d_red_circles_zsize.png
added	pygmt/tests/baseline/test_plot3d_scalar_xyz.png
added	pygmt/tests/baseline/test_plot3d_sizes.png
added	pygmt/tests/baseline/test_plot3d_sizes_colors_transparencies.png
added	pygmt/tests/baseline/test_plot3d_transparency.png
added	pygmt/tests/baseline/test_plot3d_varying_transparency.png
added	pygmt/tests/baseline/test_plot3d_vectors.png

Image diff(s)

• pygmt/tests/baseline/test_plot3d_colors.png

• pygmt/tests/baseline/test_plot3d_colors_sizes.png

• pygmt/tests/baseline/test_plot3d_colors_sizes_proj.png

• pygmt/tests/baseline/test_plot3d_from_file.png

• pygmt/tests/baseline/test_plot3d_matrix.png

• pygmt/tests/baseline/test_plot3d_matrix_color.png

• pygmt/tests/baseline/test_plot3d_projection.png

• pygmt/tests/baseline/test_plot3d_red_circles_zscale.png

• pygmt/tests/baseline/test_plot3d_red_circles_zsize.png

• pygmt/tests/baseline/test_plot3d_scalar_xyz.png

• pygmt/tests/baseline/test_plot3d_sizes.png

• pygmt/tests/baseline/test_plot3d_sizes_colors_transparencies.png

• pygmt/tests/baseline/test_plot3d_transparency.png

• pygmt/tests/baseline/test_plot3d_varying_transparency.png

• pygmt/tests/baseline/test_plot3d_vectors.png

Report last updated at commit e0f4a23

[weiji14]

Just one minor typo, otherwise looks fine :)