Fix typo in German README
Fix typo in German README

Replace "Wifi" with "Wi-Fi", as in English and other translations.

PR #3217 <https://github.com/Genymobile/scrcpy/pull/3217>

Signed-off-by: Romain Vimont <a1e17a20e93e5da710685444df3ad038ac66e2c9@rom1v.com>

Genymobile/scrcpy,Genymobile/scrcpy,Genymobile/scrcpy