chore(v3.2.x): release 3.2.21

[github-actions]

🤖 I have created a release beep boop

3.2.21 (2023-04-27)

Bug Fixes

• config.streaming.preferNativeHls only applies to HLS streams (#5167) (f3e9dab), closes #5166
• Ads: Fix usage of EventManager on CS (#5084) (e97264c)
• Fix fetch plugin with old implementations (#5091) (0004ade)
• Fix handling of CC when switching between codecs (#5160) (2203087)
• Fix HEAD request exception (#5194) (265829b), closes #5164
• Fix missing originalUri in response filters (#5114) (7dafd2f)
• Fix race that allows multiple text streams to be loaded (#5129) (35832b1)
• Fix selectVariantsByLabel using src= (#5154) (7e3adce)
• Handle empty media segments for Mp4VttParser (#5131) (bbaffe8), closes #4429
• HLS: Adding support for DTS Express in HLS fMP4 (#5112) (#5117) (de90328)
• Prevent bad calls to MediaSource.endOfStream (#5071) (c56bea6), closes #5070
• Tizen video error fixed by checking the extended MIME type (#4973) (426816e), closes #4634

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[github-actions]

🤖 Release is at https://github.com/shaka-project/shaka-player/releases/tag/v3.2.21 🌻