PR: Start spinner in dependencies dialog only when it's visible and make some improvements to the dialog's UI

[ccordoba12]

Description of Changes

• Increase our minimal required version of QtAwesome to 1.3.0 to do that.
• Make some UI improvements to that dialog:
  • Fix spinner color in the light theme.
  • Increase padding to 15px.
  • Add notes to a single html list.
  • Add a better title and remove icon because it doesn't look good in the task bar.
  • Set foreground color of optional/missing dependencies in light theme to white so it has good contrast.
  • Disable copy button while waiting for dependencies to be computed.
  • Change color of dependency_ok icon so that it stands out in relation to the text.

Visual changes

Before

After

Affirmation

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[pep8speaks]

Hello @ccordoba12! Thanks for updating this PR. We checked the lines you've touched for PEP 8 issues, and found:

• In the file spyder/utils/icon_manager.py:

Line 355:80: E501 line too long (98 > 79 characters)

Comment last updated at 2023-12-15 18:30:18 UTC

[dalthviz]

Thanks @ccordoba12 ! I just left a comment pointing that maybe it could be worthy to create a follow-up issue for the Find in Files segfault that was happening and that is handled here by skipping the main_widget.py file from the modules_test script.

Other than that this LGTM 👍

Edit - Also, just in case, this is how the dialog is looking when waiting:

[dalthviz]

Should we created an issue to follow-up on this file run giving a segfault?

[ccordoba12]

I don't think that's necessary because I was unable to reproduce locally the segfault generated when running this file and it seems random in CIs.