Print the exception name along with the message for custom ODB errors

[wllgrnt]

Motivation and Context

When raising and logging errors with ODB, when we hit a custom exception the error message is often difficult to understand. E.g calling str() on a RevisionConflictException gives:

 ((objId=500000005, fieldId=117, isIndexValue=False), (schema="testlooper_engine", typename="CommitTestDefinitionGenerationTask", fieldname="_status_history"))

When used with a general error logger it's impossible to know what the above error message is indicating. This PR modifies __str__ to include the exception name itself, which helps the user understand the nature of the issue.

Also adds a MultipleViewError to throw instead of a base Exception when applicable.

How Has This Been Tested?

pytest

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[atzannes]

For better or worse, that's normal python behavior, so let's keep it that way