Provide better UX when user's python version has changed.

When a user updates the python version that BinaryNinja points to the failure condition can be confusing. We do provide an error in the log but that can be subtle and hidden by other errors on the system.

Recommended remediation:
If the python can't be found still let the python console pop up but disabled. Add some text to the effect of:

Unable to identify the libpython: "/usr/local/lib/libpython3.9.so"  

Bonus points: @toolCHAINZ suggested we should throw the settings drop down for selecting the python interpreter right there in the widget for even better UX.

Start by reproducing the failure after changing the Python version Binary Ninja points to, then trace how the Python console handles an unidentified libpython such as "/usr/local/lib/libpython3.9.so". Done means the console still opens in a disabled state with a visible error, with the interpreter-selection settings available if that bonus behavior is implemented.