Fixing markdown parsing on settings

[Bestora]

• Resolves: [Bug]: [object Object] show in place of headings on 'Your apps' page, app details panel, description tab #48661

Summary

The custom markdown renderer heading for "marked" used fn(text,level).

In the docs it's this:
https://marked.js.org/using_pro
heading({ tokens, depth }: Tokens.Heading): string;

interface Heading {
	type: "heading";
	raw: string;
	depth: number;
	text: string;
	tokens: Token[];
}

Before:

After:

TODO

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)

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[am-hachim]

I checked the content of your branch, and the changes have been made.