This PR fixes tests for Windows binaries using Wine:
$ cmake -S . -B ../mingw -DCMAKE_TOOLCHAIN_FILE=cmake/x86_64-w64-mingw32.toolchain.cmake
$ cmake --build ../mingw
$ cmake --build ../mingw -t check
Test project /home/hebasto/git/secp256k1/mingw
Start 1: noverify_tests
Could not find executable noverify_tests
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