[PATCH v2 0/2] MR4071: msvcrt/tests: Add tests for wcsdup.

[Alex Henrie (＠alexhenrie)]

These tests are to resolve the concerns about relying on the tested behaviors, that were brought up at <https://gitlab.winehq.org/wine/wine/-/merge_requests/4060#note_48218>.

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  v2: msvcrt/tests: Add tests for wcsdup.
      msvcrt/tests: Check errno after strdup(NULL).
 
https://gitlab.winehq.org/wine/wine/-/merge_requests/4071