The "@storybook/addon-mdx-gfm" addon is meant as a migration assistant for Storybook 7.0, providing Github Flavored Markdown support to Storybook docs.
Note: This addon will likely be removed in a future version.
It's recommended you read this document and follow its instructions instead: https://storybook.js.org/docs/writing-docs/mdx#markdown-tables-arent-rendering-correctly
Once you've made the necessary changes, you can remove the addon from your package.json and storybook config.