Add null host name check in WSMan

[iSazonov]

PR Summary

Add null check for host name before path normalization.

PR Context

Fix #11278

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[PaulHigin]

LGTM

[anmenaga]

CodeFactor issues are false positives.

[ghost]

🎉v7.0.0-rc.2 has been released which incorporates this pull request.:tada:

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