app: bump SDK version to 30
app: bump SDK version to 30

It appears the smart people working at Google have realized
that direct file access is at least partially without alternative.
Paraphrasing up-to-date documentation: "To access files from the NDK
using direct paths: 1. Access them using the direct file path"

However this only applies to media files (what constitutes one
is left unspecified [1]) and some folders appear to be excluded
depending on which app Android thinks "owns" it.
This means this change doesn't totally break mpv-android but a
permanent solution will still be needed.

[1]: Word is .ass/.ssa used to be missing from this whilelist.

mpv-android/mpv-android,mpv-android/mpv-android,mpv-android/mpv-android,mpv-android/mpv-android,mpv-android/mpv-android