Add a encrypted video stream for integration test of video_player's iOS 16 bug

[hellohuanlin]

This is for integration test of the video_player's iOS 16 bug. Will be used in flutter/plugins#6442.

The key is generated using:

openssl rand 16 > encrypted_bee.key

The key_info is (used locally for the ffmpeg cmd only):

https://flutter.github.io/assets-for-api-docs/assets/videos/hls/encrypted_bee.key
encrypted_bee.key

And the m3u8 is created using:

ffmpeg -i bee.mp4 -g 60 -hls_time 2 -hls_list_size 0 -hls_segment_size 500000 -hls_key_info_file key_info encrypted_bee.m3u8

List which issues are fixed by this PR. You must list at least one issue.

flutter/flutter#111457

Also fixes flutter/flutter#112114

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• I listed at least one issue that this PR fixes in the description above.
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[hellohuanlin]

This is a random key, generated with

openssl rand 16 > encrypted_bee.key

[jmagman]

See also #178 for similar PR.

Analyzer warnings are unrelated, filed flutter/flutter#112114

[jmagman]

LGTM once analyzer is happy on deprecated usage

[hellohuanlin]

theres no autosubmit label. i will just manually land it