SPEC 0: Set minimum required version to NumPy 1.24+

[weiji14]

Description of proposed changes

Following SPEC0 policy where NumPy 1.23 is to be dropped on or after 21 June 2024 (in a minor version increment, i.e. for PyGMT v0.13.0). Bumps minimum supported NumPy version to 1.24 in the pyproject.toml, requirements.txt and environment.yml files. Also update doc/minversions.md to mention NumPy 1.24+ requirement.

This is in line with PyGMT's policy on SPEC0 at https://www.pygmt.org/v0.12.0/maintenance.html#dependencies-policy, xref #2863.

Supersedes #2991.

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.

Slash Commands

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specific operations. Supported slash command is:

• /format: automatically format and lint the code