--[Bugfix] - Fix attributes save

[jturner65]

This PR addresses when an attributes filename has to be constructed from its handle. One of the paths to do this looked for the attributes' original file directory in its handle, and then removed that directory +1 from the handle to account for the once-missing trailing slash.

However, PR #2541 modified the fileDirectory that is stored in the attributes to include the trailing slash, which required the modifications in this PR.

This also fixes a minor attributes issue where a boolean default value is not set as an init value (i.e. so it won't be written out to json if it is not changed).

Motivation and Context

How Has This Been Tested

Locally c++ and python

Types of changes

• Docs change / refactoring / dependency upgrade
• 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 change)

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have completed my CLA (see CONTRIBUTING)
• I have added tests to cover my changes.
• All new and existing tests passed.

[0mdc]

LGTM! Thank you!