Don't forbid https as a git protocol when using proxies.

modules/ksb/BuildContext.pm

@@ -967,7 +967,7 @@ sub getProjectDataReader
         croak_runtime("kde-projects repository information could not be downloaded: $!");
 
     my $protocol = $self->getOption('git-desired-protocol') || 'git';
-    if (!list_has(['git', 'http'], $protocol)) {
+    if (!list_has(['git', 'http', 'https'], $protocol)) {
         error (" b[y[*] Invalid b[git-desired-protocol] $protocol");
         error (" b[y[*] Try setting this option to 'git' if you're not using a proxy");
         croak_runtime ("Invalid git-desired-protocol: $protocol");