Include all python modules to sdk

If the toolchain is added to PATH, the python needs to have enough
modules to able to build QtWebEngine.

Task-number: QTEE-824
Change-Id: I2c9f977118f70928735eb7663d272364c5fa6754
Reviewed-by: Andras Becsi <andras.becsi@theqtcompany.com>
Reviewed-by: Eirik Aavitsland <eirik.aavitsland@theqtcompany.com>