use textarea for texeditor sidebar field

[Aryan20]

Description

If a sidebar field is a text editor field in ERPNext then that case is not handled, making it fallback to a simple input field.
The more acceptable approach is to use a textarea instead.
Text area allows expanding it's size, making it more readable aswell.

Screenshot/Screencast

Before

After

Checklist

• I have carefully reviewed the code before submitting it for review.
• This code is adequately covered by unit tests to validate its functionality.
• I have conducted thorough testing to ensure it functions as intended.
• A member of the QA team has reviewed and tested this PR (To be checked by QA or code reviewer)

Ref #89