[Data] Fix brain regions spelling (sentence case)

[ayimaok]

Environment

ALL

Description

Once the new subtrees were added to the brain regions, the sentence case spelling of the brain region names was fixed on the frontend. However, the spelling should be fixed on the entitycore-side.

To Reproduce

Steps to reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Acceptance criteria

• Include a checkbox list
• Include a checkbox list
• Include a checkbox list

Right panel fields

Type

Bug

Projects

Select 'OBI 2025-' project (plus others as relevant)
Priority: P0 (higher), P1, or P2 (lower)
Time estimate: In days

[ayimaok]

@bilalesi fyi, please edit whatever needs editing :) thanks.

[evakennyobi]

Could be fixed