Stop new Snippet form querying snippets

Summary

When viewing the new snippet form (https://gitlab.com/-/snippets/new) a GraphQL query is made to query snippets, passing in an ids variable value of "" (because the Snippet is a new record).

Currently this does not result in any issues, but with the introduction of the GlobalIDType for Snippets (#259651 (closed)), this will result in an invalid query which will cause errors in the view.

The query does not need to be executed for the "new" form, so my suggestion would be to only execute it for the "edit" variation.

Steps to reproduce

  1. Open network inspector
  2. Visit https://gitlab.com/-/snippets/new
  3. Inspect the POST graphql request

What is the current bug behavior?

GetSnippetQuery is executed when attempting to create a new snippet

What is the expected correct behavior?

That query should only be executed on "edit"

Relevant logs and/or screenshots

Screenshot_2020-10-20_at_16.14.21

Screenshot_2020-10-20_at_16.14.38

Output of checks

This bug happens on GitLab.com

Possible fixes

I guess either separating the new and edit forms into their own components, or modifying the snippets mixin to only execute the query for edit, but I'm not sure if the latter is possible - my Vue knowledge is very limited 😅