Add test to shared component in web ide - part 1/2

Issue: #198729 (closed) Regression Issue: #197493 (closed)

What does this MR do?

This MR increases the test converge for changed_file_icon and file_row.vue within the vue_shared folder.

There was a recent regression due this MR > !22364 (merged) that caused some severe issues.

Step 1: Refactored recursive part of file_row to file_tree > this MR

Step 2: Fill in slot for ide file row & remove unused prop from file_row > !23911 (closed)

Screenshots

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

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team

Closes #198729 (closed)