[FE] Update snippetBlobContent GraphQL query to fetch `blobs` instead of `blob`
After switching to multi-file support in snippets, we should expect array of blobs blobs
to be returned from the endpoint together with singular blob
that is just the first blob in the sequence. Currently, it's not broken as we do not allow multiple files on a snippet. However, after we enable :snippet_multiple_files
feature flag, the current solution will result in duplicated content for all blobs
To fix this, we should switch app/assets/javascripts/snippets/queries/snippet.blob.content.query.graphql
from singular blob
to array of blobs
Edited by Francisco Javier López (ex-Gitlab)