Update fig.contour baseline images for GMT 6.2.0rc1

[seisman]

Description of proposed changes

Address #1217

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
modified	pygmt/tests/baseline/test_contour_from_file.png
modified	pygmt/tests/baseline/test_contour_matrix.png
modified	pygmt/tests/baseline/test_contour_vec.png

Image diff(s)

Added images

Modified images

Path	Old	New
test_contour_from_file.png
test_contour_matrix.png
test_contour_vec.png

Report last updated at commit 9a76222

[weiji14]

There is an interim failure on the Windows Python 3.9 / NumPy 1.20 test at https://github.com/GenericMappingTools/pygmt/pull/1234/checks?check_run_id=2414981771#step:7:21, but I think it should be fine as all the other tests pass.