Change create-or-update-comment@v3 parameter reaction-type to reactions

[weiji14]

Description of proposed changes

Parameter name 'reaction-type' is now 'reactions', see peter-evans/create-or-update-comment#29

Fixes warning on running /format like Unexpected input(s) 'reaction-type', valid inputs are ['token', 'repository', 'issue-number', 'comment-id', 'body', 'body-path', 'body-file', 'edit-mode', 'append-separator', 'reactions', 'reactions-edit-mode'], see e.g. https://github.com/GenericMappingTools/pygmt/actions/runs/6006824531

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 wrapping a new module, open a 'Wrap new GMT module' issue and submit reasonably-sized PRs.
• If adding new functionality, add an example to docstrings or tutorials.
• Use underscores (not hyphens) in names of Python files and directories.

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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