build(deps): bump craft-providers to 1.20.1

[mr-cal]

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This resolves a bug introduced in 1.16.0 where improperly set-up base instances would cause snapcraft to fail with the error Instance setup failed. Check LXD logs for more details.

Changelog

1.20.1

• Update base compatibility tag from base-v3 to base-v4
• If an existing base instance is not setup, then it is auto-cleaned.
  If the process that created the not setup base instance is inactive, then
  craft-providers will immediately auto-clean the instance.

1.20.0

• Snaps injected from the host will have their base snap injected into
  the instance.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (9b5c2f4) 94.88% compared to head (fe9e7ba) 94.88%.

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Additional details and impacted files

@@              Coverage Diff               @@
##           hotfix/7.5    #4462      +/-   ##
==============================================
- Coverage       94.88%   94.88%   -0.01%     
==============================================
  Files             658      658              
  Lines           55192    55192              
==============================================
- Hits            52369    52367       -2     
- Misses           2823     2825       +2     

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[mr-cal]

Merging with core18 spread test failures because they are unrelated (flutter/flutter#133881)