[REF] travis_install_nightly: Force to use compatible versions of cryptography pyOpenSSL for all Odoo versions

[moylop260]

The last fixes even raised the following error:

• AttributeError: module 'lib' has no attribute 'X509_get_notBefore'

I just realized odoo-sh v13.0, v14.0 and v15.0 is using the following versions:

• cryptography==2.8 pyOpenSSL==19.0.0

I already tested v12.0 and even if they are using different versions these are working well

So using the best combination of packages compatible for all versions for now

in order to avoid raising compatibility errors