Fix botan_bcrypt_is_valid return code. Currently it returns 0 on success and BOTAN_FFI_ERROR_EXCEPTION_THROWN otherwise, which is a bit inaccurate and not consistent with the rest of the FFI interface.
Fix botan_bcrypt_is_valid return code.
Currently it returns 0 on success and BOTAN_FFI_ERROR_EXCEPTION_THROWN otherwise,
which is a bit inaccurate and not consistent with the rest of the FFI interface.

Rohde-Schwarz-Cybersecurity/botan,Rohde-Schwarz-Cybersecurity/botan,Rohde-Schwarz-Cybersecurity/botan,webmaster128/botan,webmaster128/botan,randombit/botan,webmaster128/botan,randombit/botan,Rohde-Schwarz-Cybersecurity/botan,Rohde-Schwarz-Cybersecurity/botan,webmaster128/botan,randombit/botan,Rohde-Schwarz-Cybersecurity/botan,randombit/botan,randombit/botan,webmaster128/botan