Documentation Fix: Correct cacheTag Function Usage (#71912)

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## What?

### Documentation Fix: Correct `cacheTag` Function Usage

**Issue**: The [current
documentation](https://nextjs.org/docs/canary/app/api-reference/functions/cacheTag#notes)
incorrectly states that `cacheTag` accepts an array of tags. However,
the [source
code](https://github.com/vercel/next.js/blob/ca5f29d81b011c3a01e2372118b29836f1df0fa7/packages/next/src/server/use-cache/cache-tag.ts#L4C1-L4C52)
implementation uses rest parameters (`...tags: string[]`), expecting
individual string arguments rather than an array.

**Changes**:
Updated the "Notes" section to reflect the function's correct usage:

## Why?

This change:
1. Aligns with the actual implementation in the source code
2. Prevents TypeScript errors when users follow the documentation
3. Provides clearer guidance on using the function with both direct
arguments and arrays (using the spread operator)

The current documentation might lead developers to encounter the
TypeScript error:
> "Argument of type 'string[]' is not assignable to parameter of type
'string'"

## Related

Fixes #71901

Co-authored-by: Delba de Oliveira <[email protected]>

docs/02-app/02-api-reference/04-functions/cacheTag.mdx

@@ -132,5 +132,5 @@ export async function updateBookings() {
 - **Multiple Tags**: You can assign multiple tags to a single cache entry by passing an array to `cacheTag`.
 
 ```tsx
-cacheTag(['tag-one', 'tag-two'])
+cacheTag('tag-one', 'tag-two')
 ```