Update mssqlserver-18456-database-engine-error.md (#10023)

Ran into 18456, Severity: 14, State: 62 today and can confirm that State 62 is specific to contained databases. We haven't found exact root cause yet, but having this table updated with an entry for State 62 will help point others in the direction of contained databases.  External post that helped point us in the right direction: https://sqlblog.org/2020/07/28/troubleshooting-error-18456

Author: treytMSFT

docs/relational-databases/errors-events/mssqlserver-18456-database-engine-error.md

@@ -174,6 +174,7 @@ To increase security, the error message that is returned to the client deliberat
 | 18 | Password must be changed. |
 | 38, 46 | Couldn't find database requested by user. |
 | 58 | When SQL Server is set to use Windows Authentication only, and a client attempts to log in using SQL authentication. Another cause is when SIDs don't match. |
+| 62 | Occurs when a Windows Authentication account tries to access a contained database, and the contained database exists, but the SIDs do not match. |
 | 102 - 111 | Azure AD failure. |
 | 122 - 124 | Failure due to empty user name or password. |
 | 126 | Database requested by user doesn't exist. |