FIX: docs build failure

[bdougie]

Description

[ What changed? Feel free to be brief. ]

While reviewing my build failure on #6152 I saw it was unrelated so I opened this PR.

1. Identified the problem: The vLLM documentation file was using <Tabs> and <TabItem> components without importing them
2. Found the solution: I looked at other .mdx files in the documentation to see how they import these components
3. Applied the fix: I added the missing imports at the top of the file:

   import TabItem from "@theme/TabItem";
   import Tabs from "@theme/Tabs";
   

The documentation build now works correctly with all the tab components properly imported and functional.

Checklist

• [x] I've read the contributing guide
• [x] The relevant docs, if any, have been updated or created
• [x] The relevant tests, if any, have been updated or created

Screenshots

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Tests

[ What tests were added or updated to ensure the changes work as expected? ]