[Cherry-pick] DYN-9879: Py Engine Change pops up erroneously

[github-actions]

Cherry-pick of #16747 to RC4.0.0_master

Purpose

This PR addresses DYN-9879.

Fixes an issue where the “Hide Python engine change notifications” preference did not persist reliably.
Also ensures that WorkspaceModel.ShowPythonAutoMigrationNotifications is reset to false when creating new workspaces.

Declarations

Check these if you believe they are true

• Is documented according to the standards
• The level of testing this PR includes is appropriate
• Changes to the API follow Semantic Versioning and are documented in the API Changes document.

Release Notes

Fixes an issue where the “Hide Python engine change notifications” preference did not persist reliably.
Also ensures that WorkspaceModel.ShowPythonAutoMigrationNotifications is reset to false when creating new workspaces.

Reviewers

@zeusongit
@DynamoDS/eidos

FYIs

@dnenov
@achintyabhat
@jnealb