[DYN-6760] Updating Unclear note of "Code Block" node in Strings sample

[Edward-Chaplin]

Purpose

This PR address DYN-6760. It updates the note for the Code Block node in the strings example.

Before:

After:

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
• This PR contains no files larger than 50 MB

Release Notes

Updating the Core_String.dyn sample file. Specifically updating a note under the "Create String" example to finish off the text within the note.

Reviewers

@dnenov
@achintyabhat
@QilongTang

Informed
@Amoursol

[github-actions]

See the ticket for this pull request: https://jira.autodesk.com/browse/DYN-6760