Remove the unimplemented CloseIC in fcitx module

This call is actually a left-over when porting from fcitx4 service to the new org.freedesktop.portal.Fcitx supported by both fcitx4/fcitx5. CloseIC is actually never a part of the new interface on org.freedesktop.portal.Fcitx. It cause any issue user visible effect.

src/core/linux/SDL_fcitx.c

@@ -401,7 +401,6 @@ void SDL_Fcitx_SetFocus(SDL_bool focused)
 void SDL_Fcitx_Reset(void)
 {
     FcitxClientICCallMethod(&fcitx_client, "Reset");
-    FcitxClientICCallMethod(&fcitx_client, "CloseIC");
 }
 
 SDL_bool SDL_Fcitx_ProcessKeyEvent(Uint32 keysym, Uint32 keycode, Uint8 state)