Fixes #8: Any active plugin in a category returns copy of the original array and throws an error on frontend

[jeawhanlee]

Description

This PR fixes the issue of an error notice when the 2nd or last plugin is activated in the category also it fixes the issue where the optimize category is pushed to the last.

Fixes #8

Type of change

• Bug fix (non-breaking change which fixes an issue).

Detailed scenario

• on this Closes #6877 Create a new tab in WP Rocket wp-rocket#7047
• go to the plugins tab
• Install termly
• See that backwpup is not throwing an error.

Technical description

Documentation

In this change, We updated the original array by making reference to it directly and also kept the optimize category at the top for wp rocket by checking if the active plugin is not the main plugin.

New dependencies

N/A

Risks

N/A

Mandatory Checklist

Code validation

• I validated all the Acceptance Criteria. If possible, provide screenshots or videos.
• I triggered all changed lines of code at least once without new errors/warnings/notices.
• I implemented built-in tests to cover the new/changed code.

Code style

• I wrote a self-explanatory code about what it does.
• I protected entry points against unexpected inputs.
• I did not introduce unnecessary complexity.