Improve edge case coverage of load_node magic

[noklam]

Description

Fix #5417, there are details what this PR try to fix. In addition, the test case should be self-explanatory test_load_node_executes_with_same_module_helper_dependency

Development notes

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Checklist

• Read the contributing guidelines
• Signed off each commit with a Developer Certificate of Origin (DCO)
• Opened this PR as a 'Draft Pull Request' if it is work-in-progress
• Updated the documentation to reflect the code changes
• Added a description of this change in the RELEASE.md file
• Added tests to cover my changes
• Checked if this change will affect Kedro-Viz, and if so, communicated that with the Viz team