feat!: upgrade to MDX v2

[mrazauskas]

Docusaurus is upgrading to MDX v2 (reference facebook/docusaurus#8288).

This plugin should support MDX v2 as well to be ready for Docusaurus v3 (facebook/docusaurus#8469).

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See also the documentation PR: facebook/docusaurus#8941.

[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (b890c75) 100.00% compared to head (e77e103) 100.00%.

❗ Current head e77e103 differs from pull request most recent head fe11c64. Consider uploading reports for the commit fe11c64 to get more accurate results

Additional details and impacted files

@@            Coverage Diff            @@
##              main      #164   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files            2         2           
  Lines           64        66    +2     
  Branches        21        21           
=========================================
+ Hits            64        66    +2     

Impacted Files	Coverage Δ
src/plugin.js	100.00% <100.00%> (ø)

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[slorber]

Hi

FYI Docusaurus v3 will finally be on mdx v3, a new major without many breaking changes, it should be relatively easy to make this plugin compatible

[mrazauskas]

Thanks for heads up.

Just gave it a try (see #210) and all tests are passing with remark-mdx v3. That was really easy (;