Quote LIBCRYPTO_PATH for dynamic load test

[WillChilds-Klein]

Summary

• Pass LIBCRYPTO_PATH as a quoted string literal at the CMake level (-DLIBCRYPTO_PATH=\"...\") so it can be consumed directly by the test as a const char *.
• Remove the now-redundant xstr/str stringification macros and DYNAMIC_LIBRARY_PATH indirection in dynamic_loading_test.c, using LIBCRYPTO_PATH directly.

Why

Stringification via #/xstr does not handle paths containing characters that aren't valid in C identifiers/tokens (e.g., spaces, hyphens in some contexts). Quoting at the compile-define level is more robust and lets the test consume the macro as-is.

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[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 78.18%. Comparing base (6f246af) to head (3455dcb).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3259      +/-   ##
==========================================
+ Coverage   78.15%   78.18%   +0.02%     
==========================================
  Files         689      689              
  Lines      123678   123678              
  Branches    17192    17193       +1     
==========================================
+ Hits        96663    96696      +33     
+ Misses      26097    26064      -33     
  Partials      918      918              

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