[release/8.0] Support Windows based ECDSA SignedCms #91247
                
     Merged
            
            
          
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Backport of #91183 to release/8.0
/cc @jeffhandley @jborean93
Customer Impact
Reported by multiple customers at #77377. Customers that created a signed CMS using .NET Framework or Win32 APIs using an ECDSA key or certificate will not validate in .NET (Core). This hinders compatibility between .NET Framework / Win32 and .NET.
This change fixes the validation to be compatible with .NET Framework.
Testing
A unit test was introduced to verify the correct behavior and to prevent regressions.
Risk
Low. This is a small change that is not logically complex.