Convert base64 string to byte array.
input bytes base64 representation
input: 'yc2LYup'output: [0xc9, 0xcd, 0x8b, 0x62, 0xea] Copy
input: 'yc2LYup'output: [0xc9, 0xcd, 0x8b, 0x62, 0xea]
Convert base64 string to byte array.