Fix incorrect width of APCu Hit/Miss bar

[lukasbableck]

Description

The width of the APCu Miss bar in the Hit/Miss graph on the APCu info page is calculated incorrectly, resulting in both bars always being the same width. This PR fixes that issue.

Before:

After:

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

1. Make change
2. See bars with correct width

Test Configuration:

• Distribution: Debian 12
• Webserver: Nginx
• PHP: 8.3 FPM
• etc.etc.:

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes