Use an uncompressed omni.ja to improve final apk compression.

This was something in the back of my head for some time and finally today I got to check: if we (re)zip omni.ja with no compression at all, we allow 7z to do a better deflate job while packaging the apk (and as a side effect, the crash on startup is gone too).

Comparing current alpha build vs this one we get ~600KB less than trying to optimize omni.ja's own compression and apparently no compatibility issues (tested on the stable branch as well).

ma1@tb-build-02:~/tor-browser-build$ apk=/public_html/builds/torbrowser/alpha/unsigned/13.5a5-build1/tor-browser-qa-android-aarch64-13.5a5.apk; echo $(($(stat -c %s ~richard/$apk) - $(stat -c %s ~ma1/$apk))) 
602112

Filing a MR right away.