Always synchronize clipboard on explicit COPY/CUT

If --no-clipboard-autosync is enabled, the automatic clipboard
synchronization performed whenever the device clipboard changes is
disabled.

But on explicit COPY and CUT scrcpy shortcuts (MOD+c and MOD+x), the
clipboard should still be synchronized, so that it remains possible to
copy-paste from the device to the computer.

This is consistent with the behavior of MOD+v, which pastes the computer
clipboard to the device.

Refs #2228 <https://github.com/Genymobile/scrcpy/issues/2228>
Refs #2817 <https://github.com/Genymobile/scrcpy/pull/2817>
PR #2834 <https://github.com/Genymobile/scrcpy/pull/2834>