bug: Size unit color changes when --color-scale=age --color-scale-mode=fixed is used

[ghost]

Another --color-scale bug: I would expect when using --color-scale=age, --color-scale-mode should not affect the display of file size. But it does: --color-scale-mode=fixed changes the color of the size units:

Note that specifying gradient (the default anyway) doesn't affect the size units.

Normally I use EXA_COLORS since bright yellow is unreadable in my terminal theme, but here I have it unset.

May or may not have something to do with #633 and #682.

$ eza --version
eza - A modern, maintained replacement for ls
v0.16.0 [+git]
https://github.com/eza-community/eza
$ hostnamectl 
 Static hostname: rich-holmes-desktop
       Icon name: computer-desktop
         Chassis: desktop
      Machine ID: ...
         Boot ID: ...
Operating System: Linux Mint 21.2                 
          Kernel: Linux 5.15.0-88-generic
    Architecture: x86-64
 Hardware Vendor: System76
  Hardware Model: Wild Dog Pro

[MartinFillon]

Gonna make a PR later but fixed it locally