LedgerX: several tests broken

[Sjors]

Several tests have been temporarily disabled by #795:

• test_signtx
• test_big_tx
• test_display_address_path
• test_display_address_descriptor
• test_sign_msg

The tests pass for legacy but not for the NanoX.

They all seem to revolve around user interaction, so perhaps one of the strings doesn't match?

[Sjors]

cc @bigspider

[Sjors]

I opened #809 as a simple demonstration of the test failure on top of recent CI improvements.