Fix incorrect hiding of inline comment cells

What does this MR do?

Fixes an issue where the "new comment" form does not render in the new unified component inline view. To test this you will need to enable both unified_diff_components and unified_diff_lines feature flags.

In rails console:

Feature.enable(:unified_diff_lines, Project.find_by_full_path("h5bp/html5-boilerplate"))
Feature.enable(:unified_diff_components, Project.find_by_full_path("h5bp/html5-boilerplate"))

Screenshots (strongly suggested)

Broken

Screen_Recording_2020-11-13_at_1.33.50_PM

Fixed

Screen_Recording_2020-11-13_at_1.32.22_PM

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

Related to: #236075 (closed)