Add E2E for personal snippet with multiple files
What does this MR do?
Adds a new end-to-end to create a personal snippet with multiple files.
See gitlab-org/quality/testcases#842 (closed) and &2829 (closed)
NB the test enables :snippet_multiple_files
feature flag and cannot be run in live environments.
Does this MR meet the acceptance criteria?
Conformity
Edited by Anastasia McDonald