Fix for type conversion error

[lealem47]

Description

Fix for warning below

wolfcrypt\test\test.c(24886,50): warning C4267: 'function': conversion from 'size_t' to 'word32', possible loss of data

Testing

Reproduced and resolved locally

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[dgarske]

@lealem47 Are you able to share steps to reproduce? Was this the only one you found?

[lealem47]

@lealem47 Are you able to share steps to reproduce? Was this the only one you found?

@dgarske Reproduced by adding #define USE_CERT_BUFFERS_2048 to the user_settings.h in the Windows sln build. This was the only warning reported.