docs: add bun to installation methods

[kul-sudo]

Please describe the changes this PR makes and why it should be merged:
The PR adds bun to the installation methods Million can be installed with.

Status

• Code changes have been tested against prettier, or there are no code changes
• I know how to update typings and have done so, or typings don't need updating

Semantic versioning classification:

• This PR changes the codebase
  • This PR includes breaking changes (methods removed or renamed, parameters moved or removed)
  • This PR changes the internal workings with no modifications to the external API (bug fixes, performance improvements)
• This PR only includes non-code changes, like changes to documentation, README, etc.

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Name	Status	Preview	Comments	Updated (UTC)
million-kitchen-sink	✅ Ready (Inspect)	Visit Preview	💬 Add feedback	Sep 10, 2023 1:00pm
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[CLAassistant]

All committers have signed the CLA.

[aidenybai]

big fast, i like

[kul-sudo]

big fast, i like

Yeah 😅