Bug: repeated plugin conflict printed with mdformat-footnote

[jamesbraza]

Describe the bug

context

pip install mdformat mdformat-myst mdformat-footnote
mdformat .

expectation

I expected no warnings.

bug

The repeated warnings get printed 10's of times:

> mdformat .
Warning: Plugin conflict. More than one plugin defined a renderer for "footnote" syntax.
Warning: Plugin conflict. More than one plugin defined a renderer for "footnote_ref" syntax.
Warning: Plugin conflict. More than one plugin defined a renderer for "footnote_block" syntax.

problem

The warning should not print tens of times.

Reproduce the bug

See above box.

List your environment

markdown-it-py       2.2.0
mdformat             0.7.16
mdformat_footnote    0.1.1
mdformat_frontmatter 2.0.1
mdformat_myst        0.1.5
mdformat_tables      0.4.1
mdit-py-plugins      0.3.5
mdurl                0.1.2
pip                  23.1.2
ruamel.yaml          0.17.26
ruamel.yaml.clib     0.2.7
setuptools           65.5.0
tomli                2.0.1

[welcome[bot]]

Thanks for opening your first issue here! Engagement like this is essential for open source projects! :hugs:
If you haven't done so already, check out EBP's Code of Conduct. Also, please try to follow the issue template as it helps other community members to contribute more effectively.
If your issue is a feature request, others may react to it, to raise its prominence (see Feature Voting).
Welcome to the EBP community! :tada: