[Bug] SerializeAdalV3 returns null when Id Token has no oid claim

[bgavrilMS]

Scenario: web site

This is an ADAL 2 MSAL migration issue. Partner is using SerializeAdalV3 logic which in some cases returns null. This caused the partner to revert back from MSAL to ADAL.

It looks like in rare cases the IdToken does not have oid claim. ADAL uses sub claim when oid is not available.