gh-154587: Fix Windows buffer declaration in _cursesmodule

[BHUVANSH855]

Summary

Fix a Windows-only buffer declaration in Modules/_cursesmodule.c.

The code incorrectly declared:

char *buffer[100];

which creates an array of 100 char * pointers. However, the buffer is passed to PyOS_snprintf(), which expects a writable char * character buffer. This change replaces it with:

char buffer[100];

which matches the intended usage and resolves the clang-cl incompatible pointer type compilation error reported in gh-154587.

Closes gh-154587.