Allow to delete value streams with GraphQL

What does this MR do and why?

Allow to delete value streams with GraphQL

Add GraphQL mutation to delete value streams.

part of #410340 (closed)

How to set up and validate locally

1. Follow these steps to create a value stream using Graphql and take a note of its global id.
2. Use the following mutation:

mutation deleteValueStream {
  valueStreamDestroy(input: { id: VALUE_STREAM_GLOBAL_ID  }) {
    valueStream {
      id
      name
    }
    errors
  }
} 

MR acceptance checklist

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