fix: insert note index #undefined in case missing tags

[huland]

Community PR Review Checklist

Problem description

• When insert note index command runs it collects the active note's child notes.
• These notes will be checked with the condition which was modified.
• The condition checked if the note's name startsWith "tags".
• If it was true, the next line splits the note's name at "tags." and returns the 1st element (without checking the result of the split).

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  Related to: Insert note index includes #undefined in the list when run in the root.md note #2314

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[kevinslin]

thanks for the PR! could you elaborate on the issue this is fixing? could you also add a test case in

dendron/packages/plugin-core/src/test/suite-integ/InsertNoteIndexCommand.test.ts

Line 10 in 1f0b25a

import { WSUtils } from "../../WSUtils";

?

[huland]

I added:

• description about the issue; see PR's "problem description" section
• test cases

[hikchoi]

test update looks good.
I approved the CI run and it looks good, but would be good to rebase to the latest master and check that the CI runs okay as well.

[huland]

test update looks good. I approved the CI run and it looks good, but would be good to rebase to the latest master and check that the CI runs okay as well.

Thank you. I did rebase the latest master.

[kevinslin]

this looks great! thanks for the contribution - we'll be including this in next weeks release!