Fix single file editor not working for json files

What does this MR do and why?

Fix single file editor not working for json files

• Regression was introduced in this MR.
• We need to tell axios to not transform the response
• Added test to cover this issue

Changelog: fixed

MR acceptance checklist

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Screenshots or screen recordings

Before	After

How to set up and validate locally

1. Start GDK and open a project with a .json file
2. Click Edit dropdown and Edit single file
3. Confirm that the actual content is loaded not [Object object]

Thanks

Thanks to @Taucher2003 for pairing on this with me!