Update react

[bilalesi]

1. upgrade react to 18.3 (preparation to 19.0 migration).
2. Fix code editor duplication and code mis-formatting in studio dashboard (creation).

Description

How has this been tested?

Types of changes

• 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 not work as expected)

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added necessary unit and integration tests.
• I have added screenshots (if applicable), in the comment section.

[danburonline]

A small comment about removing some leftovers; otherwise, all good! 👍