General: Make markdown editor resizable by default

[milljoniaer]

Checklist

General

• This is a small issue that I tested locally and was confirmed by another developer on a test server.
• Language: I followed the guidelines for inclusive, diversity-sensitive, and appreciative language.
• I chose a title conforming to the naming conventions for pull requests.

Client

• Important: I implemented the changes with a very good performance, prevented too many (unnecessary) REST calls and made sure the UI is responsive, even with large data.
• I followed the coding and design guidelines.
• Following the theming guidelines, I specified colors only in the theming variable files and checked that the changes look consistent in both the light and the dark theme.
• I documented the TypeScript code using JSDoc style.
• I added multiple screenshots/screencasts of my UI changes.
• I translated all newly inserted strings into English and German.

Motivation and Context

This PR closes #7385. Default behavior should be resizable markdown editors (it can still be disabled with enableResize=false).
This PR also removes unnecessary on-top built resizing for programming instruction editor.

Steps for Testing

Look for markdown editors and verify that they are resizable and look/work correctly, especially for:

• Programming instructions editor (edit/create new programming exercise)
• Code of Conduct/Registration Confirmation Message (edit/create course)

Review Progress

Code Review

• Code Review 1
• Code Review 2

Manual Tests

• Test 1
• Test 2

Test Coverage

Screenshots

programming exercise instructions:

course code of conduct:

[aplr]

Code looks good

[valentin-boehm]

lgtm

[xHadie]

Tested on Legacy TS1
No Markdown editors appear to be resizeable by default for me. I never see the resize icon in the border of the containers.

[milljoniaer]

Tested on Legacy TS1 No Markdown editors appear to be resizeable by default for me. I never see the resize icon in the border of the containers.

The markdown editors don't have the resize icon in the bottom right corner like the native textareas have it.
They have it below the editor in the center. You can see it in the screenshot of my PR description.

[max-bergmann]

Tested in testing session - LGTM

[julian-christl]

Tested on TS4, works