Make use of all Qt features conditional that are not supported on the
web assembly platform (mainly TLS support and QProcess).
Note that HTTPs is supposed to work nevertheless as long as the certificate
matches (with the usual corss-site scripting limitations).
* Unify code paths for compiling expected SSL errors so in any case the
expected errors are including the error types emitted by the Schannel
backend
* See https://github.com/Martchus/syncthingtray/issues/223