Enable Node Auto Complete in CustomNodeWorkspace

[QilongTang]

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Purpose

Enable Node Auto Complete in CustomNodeWorkspace ( https://jira.autodesk.com/browse/DYN-3252).

Before this change, when opening a dyf, RequestNodeAutoCompleteSearch is unbind and never rebind. Switching from different dyns will always call workspace.loaded to rebind so the bug is buried only for dyf opening.

Declarations

Check these if you believe they are true

• The codebase is in a better state after this PR
• Is documented according to the standards
• The level of testing this PR includes is appropriate
• User facing strings, if any, are extracted into *.resx files
• All tests pass using the self-service CI.
• Snapshot of UI changes, if any.
• Changes to the API follow Semantic Versioning and are documented in the API Changes document.
• This PR modifies some build requirements and the readme is updated

Reviewers

@DynamoDS/dynamo

FYIs

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[zeusongit]

LGTM, with one comment

[zeusongit]

Are you planning to add any tests?

[QilongTang]

Are you planning to add any tests?

Yes, working on it

[QilongTang]

@zeusongit @reddyashish Unit test added. PTAL

[reddyashish]

Looks good to me.