Crash with invalid base64 data

This crash always happens if the base64 data is not 100% valid. This happens on Android, I didn't test iOS.

toByteArray("YXNkZgo=") // works
toByteArray("YXNkZgo") // crash
toByteArray("YXNkZgo==") // crash

If it's even more corrupted, with for example invalid chars like ,&* or so, it crashes as well.

01-20 15:32:48.194  3406  3406 F DEBUG   : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
01-20 15:32:48.194  3406  3406 F DEBUG   : Build fingerprint: 'Android/sdk_phone_x86/generic_x86:11/RSR1.210210.001.A1/7193139:userdebug/dev-keys'
01-20 15:32:48.194  3406  3406 F DEBUG   : Revision: '0'
01-20 15:32:48.194  3406  3406 F DEBUG   : ABI: 'x86'
01-20 15:32:48.194  3406  3406 F DEBUG   : Timestamp: 2023-01-20 15:32:48+0100
01-20 15:32:48.194  3406  3406 F DEBUG   : pid: 3238, tid: 3298, name: mqt_js  >>> com.jblapp <<<
01-20 15:32:48.194  3406  3406 F DEBUG   : uid: 10136
01-20 15:32:48.194  3406  3406 F DEBUG   : signal 6 (SIGABRT), code -6 (SI_TKILL), fault addr --------
01-20 15:32:48.194  3406  3406 F DEBUG   :     eax 00000000  ebx 00000ca6  ecx 00000ce2  edx 00000006
01-20 15:32:48.194  3406  3406 F DEBUG   :     edi e739c81e  esi b426a940
01-20 15:32:48.194  3406  3406 F DEBUG   :     ebp e99beb90  esp b426a8e8  eip e99beb99
01-20 15:32:48.253  3406  3406 F DEBUG   : backtrace:
01-20 15:32:48.253  3406  3406 F DEBUG   :       #00 pc 00000b99  [vdso] (__kernel_vsyscall+9)
01-20 15:32:48.253  3406  3406 F DEBUG   :       #01 pc 0005ad68  /apex/com.android.runtime/lib/bionic/libc.so (syscall+40) (BuildId: 6e3a0180fa6637b68c0d181c343e6806)
01-20 15:32:48.253  3406  3406 F DEBUG   :       #02 pc 00076511  /apex/com.android.runtime/lib/bionic/libc.so (abort+209) (BuildId: 6e3a0180fa6637b68c0d181c343e6806)
01-20 15:32:48.253  3406  3406 F DEBUG   :       #03 pc 000b783c  /data/app/~~fW1sq5DMEO4DOlGQyVjpDw==/com.jblapp-J8UQIcQPuouGruyooLoyiA==/lib/x86/libc++_shared.so (BuildId: 5d632b8bdfc3c6b26faedb2f035955edb77efe9b)
...

Start by reproducing the Android crash through the toByteArray entry point with the valid, missing-padding, extra-padding, and invalid-character examples in the issue. Inspect the implementation and verify that each invalid input no longer crashes, then add or run the relevant checks available in the project.