fix: correct typo in DRM CDM error message (#1328)

### Description
Fix a typo in the DRM Content Decryption Module error message: "upading"
→ "updating". Updated the string in `eme-fairplay.ts`,
`webkit-fairplay.ts`, `index.ts`, and the `en.json` i18n file.

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---

> [!NOTE]
> **Low Risk**
> Low risk string-only change to a user-facing DRM error message; no
behavioral or logic changes.
> 
> **Overview**
> Fixes a typo in the DRM Content Decryption Module *internal error*
message ("upading" → "updating").
> 
> Updates the i18n key/value in `lang/en.json` and aligns the
corresponding `i18n()` callsites in `eme-fairplay.ts`,
`webkit-fairplay.ts`, and the HLS error mapping in `index.ts`.
> 
> <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit
c3424cc7bb636ddf1d6ace2b01386a19d196f92f. Bugbot is set up for automated
code reviews on this repo. Configure
[here](https://www.cursor.com/dashboard/bugbot).</sup>
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