Upgrading Orange through the add-on dialog does not work for Anaconda users

**What's wrong?**

I'm using Orange through Anaconda. By default it brings Orange 3.26 which is said to be upgradeable to Orange 3.30.2.
Here's the command to upgrade:
python -m pip install --upgrade --upgrade-strategy=only-if-needed Orange3==3.30.2

The script is reporting the following error:

ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
spyder 4.2.5 requires pyqt5<5.13, but you have pyqt5 5.15.6 which is incompatible.
spyder 4.2.5 requires pyqtwebengine<5.13, but you have pyqtwebengine 5.15.5 which is incompatible.
Successfully installed Orange3-3.30.2 PyQt5-5.15.6 PyQt5-Qt5-5.15.2 PyQt5-sip-12.9.0 PyQtWebEngine-5.15.5 PyQtWebEngine-Qt5-5.15.2 httpx-0.19.0 openTSNE-0.6.1 pyqtgraph-0.12.3

Although it looks as being correctly installed:

ubuntu@ubuntu:~$ python
Python 3.8.8 (default, Apr 13 2021, 19:58:26)
[GCC 7.3.0] :: Anaconda, Inc. on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> import Orange
>>> Orange.version.version
'3.30.2'

it produces error while trying to run the UI

ubuntu@ubuntu:~$ python -m Orange.canvas
Traceback (most recent call last):
File "/home/ubuntu/anaconda3/lib/python3.8/runpy.py", line 194, in _run_module_as_main
return _run_code(code, main_globals, None,
File "/home/ubuntu/anaconda3/lib/python3.8/runpy.py", line 87, in _run_code
exec(code, run_globals)
File "/home/ubuntu/anaconda3/lib/python3.8/site-packages/Orange/canvas/__main__.py", line 44, in
from orangecanvas.main import (
File "/home/ubuntu/anaconda3/lib/python3.8/site-packages/orangecanvas/main.py", line 23, in
from .application.canvasmain import CanvasMainWindow
File "/home/ubuntu/anaconda3/lib/python3.8/site-packages/orangecanvas/application/canvasmain.py", line 61, in
from ..help import HelpManager
File "/home/ubuntu/anaconda3/lib/python3.8/site-packages/orangecanvas/help/__init__.py", line 1, in
from .provider import HelpProvider
File "/home/ubuntu/anaconda3/lib/python3.8/site-packages/orangecanvas/help/provider.py", line 18, in
from AnyQt.QtNetwork import (
File "/home/ubuntu/anaconda3/lib/python3.8/site-packages/AnyQt/QtNetwork.py", line 51, in
from PyQt5.QtNetwork import *
ImportError: /lib/x86_64-linux-gnu/libgssapi_krb5.so.2: undefined symbol: krb5_ser_context_init, version krb5_3_MIT

**How can we reproduce the problem?**

Download and install Anaconda (Anaconda3-2021.05-Linux-x86_64.sh)
Install the Orange package from the Anaconda Navigator.
Try to upgrade Orange to latest available version 3.30.2

**What's your environment?**

- Operating system: Ubuntu
- Orange version: 3.26
- How you installed Orange: through Anaconda