travis: bump libxcb version to 1.13

Fixes following dependency problem:
  Native dependency xcb-dri3 found: NO found '1.11' but need: '>= 1.13'

Signed-off-by: Christian Gmeiner <christian.gmeiner@gmail.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>
Fixes: c80c08e22603 ("vulkan/wsi/x11: Add support for DRI3 v1.2")
1 file changed