Add missing Macros.hpp include to Error.hpp

[thewtex]

To address:

In file included from /ITKWebAssemblyInterface/include/itkPipeline.h:21:
In file included from /ITKWebAssemblyInterface-build/_deps/cli11-src/include/CLI/App.hpp:25:
In file included from /ITKWebAssemblyInterface-build/_deps/cli11-src/include/CLI/ConfigFwd.hpp:17:
/ITKWebAssemblyInterface-build/_deps/cli11-src/include/CLI/Error.hpp:75:5: error: unknown type name 'CLI11_NODISCARD'
    CLI11_NODISCARD int get_exit_code() const { return actual_exit_code; }
    ^

[codecov]

Codecov Report

Merging #755 (57b03d6) into main (65ef491) will not change coverage.
The diff coverage is n/a.

❗ Current head 57b03d6 differs from pull request most recent head 119f79e. Consider uploading reports for the commit 119f79e to get more accurate results

@@           Coverage Diff           @@
##             main     #755   +/-   ##
=======================================
  Coverage   99.46%   99.46%           
=======================================
  Files          12       12           
  Lines        3958     3958           
=======================================
  Hits         3937     3937           
  Misses         21       21           

Impacted Files	Coverage Δ
include/CLI/Error.hpp	100.00% <ø> (ø)

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[henryiii]

Thanks!