Issue Form: Add a step to check for an existing issue before posting a new issue

[KevinMulhern]

Describe your suggestion

When links go down, especially in Foundations, we get flooded with several duplicate issues about the same thing. The most recent example - https://github.com/TheOdinProject/curriculum/issues/26753

Acceptance Criteria

1. Add a step near the beginning of the issue form that reminds issue creators to check for duplicate issues before posting.

Checks

• [X] I have thoroughly read and understand The Odin Project Contributing Guide
• [ ] Would you like to work on this issue?

(Optional) Discord Name

No response

(Optional) Additional Comments

No response

[Swap2104]

I'd like to help if possible

[KevinMulhern]

Thanks @Swap2104, I've assigned this to you.

To provide a bit more detail, I think all we need is...

1. An extra check item in the "Checks" list, something like: "This is not a duplicate of an existing issue (please have a look through our open issues list to make sure)"

2. Move the checks list directly above the "Describe your suggestion" input so we prompt people to check for duplicates before they put a lot of effort into the issue.