fix: upgrade to @rollup/plugin-commonjs 21.x

[benmccann]

Description

@rollup/plugin-commonjs would hoist requires out of try/catches leading to failures

Additional context

This should fix issues like sveltejs/kit#2523. SvelteKit is being upgraded as well in sveltejs/kit#2539

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What is the purpose of this pull request?

• Bug fix
• New Feature
• Documentation update
• Other

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