Explicitly disable the configure command for eigen (ext)

[m-aXimilian]

Description

Building with clang (tested with version 18.1.0rc) yields an error in the configuration step of the external eigen package.
Explicitly disabling this (it is implicitly skipped when building with msvc) solves this problem and the project builds fine with clang on windows.

Fixes # (issue)

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 tested using clang from the official LLVM releases. Configuring the project with export CC=$(which clang) && export CXX=$(which clang++) && cmake -B build -S . -G Ninja (ensuring the which clang and which clang++ calls point to the correct locations of the compilers).
I've tested both, Release and Debug configurations + used this fork in an external project that includes libczi via FetchContent_Declare.

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 65.50%. Comparing base (ae6130d) to head (c4502be).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #115   +/-   ##
=======================================
  Coverage   65.50%   65.50%           
=======================================
  Files          86       86           
  Lines       10893    10893           
=======================================
  Hits         7136     7136           
  Misses       3757     3757           

Flag	Coverage Δ
windows-latest	65.50% <ø> (ø)

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[ptahmose]

LGTM, thanks!

I am undecided whether the version number of libCZI should be bumped or not. So far I went with the rule "if in doubt, increment the patch". I'm ok with both, but if you decide to change the version, don't forget to add a line to "version history" as well.

[m-aXimilian]

I opted for incrementing the version number. It is for sure an arguably small and potentially harmless change, but it mingles with the build environment nonetheless. Therefore, I'd say it's good to have it documented in the version history.

[ptahmose]

Please fix version number in version-history.

[ptahmose]

LGTM, thanks!