Upgrading VTU to v1: Replace deprecated `contains` method

What does this MR do?

.contains will be deprecated in @vue/test-utils 1.x. This MR contains first part of removing this deprecated method from our tests codebase

This MR was generated by extremely simple regexp

wrapper\.contains\(([^)]+)\) ==> wrapper.find($1).exists()

Screenshots

N/A

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• [-] Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done