update libcurl and enable SSL by default (on Windows)

[ptahmose]

Description

• Update the curl version to 8.9.1 (note: this only affects builds where LIBCZI_BUILD_PREFER_EXTERNALPACKAGE_LIBCURL is set to OFF)
• enable SSL by default on Windows (using SChannel)

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

locally

Checklist:

• I followed the Contributing Guidelines.
• I did a self-review.
• I commented my code, particularly in hard-to-understand areas.
• I updated the documentation.
• I updated the version of libCZI following Versioning of libCZI depending on the type of change
  • Bug fix -> PATCH
  • New feature -> MINOR
  • Breaking change -> MAJOR
• I have added tests that prove my fix is effective or that my feature works.
• New and existing unit tests pass locally with my changes.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 66.16%. Comparing base (3567211) to head (cdf38e3).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #111   +/-   ##
=======================================
  Coverage   66.16%   66.16%           
=======================================
  Files          85       85           
  Lines       10685    10685           
=======================================
  Hits         7070     7070           
  Misses       3615     3615           

Flag	Coverage Δ
windows-latest	66.16% <ø> (ø)

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