[3dprinter-general] Bug#972424: cura: Cura 4.7.1 crashes because of incompatible python3-uranium < 4.7.0

[Raphael Wimmer]

Package: cura
Version: 4.7.1-2
Severity: normal

Dear Maintainer,

Thank you for packaging Cura!

# Symptom:
After upgrading Cura from 4.5 to 4.7.1, Cura crashes with the
following error message on start:

> [MainThread] cura.CrashHandler.__init__ [66]: An uncaught error has occurred!
> [MainThread] cura.CrashHandler.__init__ [69]: Traceback (most recent call last):
> [MainThread] cura.CrashHandler.__init__ [69]:   File "/bin/cura", line 233, in <module>
> [MainThread] cura.CrashHandler.__init__ [69]:     app = CuraApplication()
> [MainThread] cura.CrashHandler.__init__ [69]:   File "/usr/lib/python3/dist-packages/cura/CuraApplication.py", line 216, in __init__
> [MainThread] cura.CrashHandler.__init__ [69]:     self._cura_API = CuraAPI(self)
> [MainThread] cura.CrashHandler.__init__ [69]:   File "/usr/lib/python3/dist-packages/cura/API/__init__.py", line 48, in __init__
> [MainThread] cura.CrashHandler.__init__ [69]:     self._connectionStatus = ConnectionStatus()
> [MainThread] cura.CrashHandler.__init__ [69]:   File "/usr/lib/python3/dist-packages/cura/API/ConnectionStatus.py", line 30, in __init__
> [MainThread] cura.CrashHandler.__init__ [69]:     self._is_internet_reachable = manager.isInternetReachable  # type: bool
> [MainThread] cura.CrashHandler.__init__ [69]: AttributeError: 'HttpRequestManager' object has no attribute 'isInternetReachable'

# Probable Reason
Cura 4.7.1 depends on python3-uranium >= 4.5.0
Therefore, upgrading from Cura 4.5 to 4.7.1 does not also upgrade
python3-uranium.

However, the `HTTPRequestManager.isInternetReachable` property has only
been added to python3-uranium after the 4.6.0 release [1].

Manually upgrading python3-uranium to 4.7.1 makes Cura start up again.

# Proposed fix

cura should require python3-uranium >= 4.7.0
(Maybe cura should also depend on python3-savitar >= 4.7.0 to avoid further incompatibilities)

Cheers (and thanks again!),

Raphael

[1] https://github.com/Ultimaker/Uranium/commit/6d699fce1a073ca424a274314aff33f436d4fa74