[FEAT] Disable fetching for specific package manager

[carterprince]

Current state:

Currently, fastfetch shows several different package managers, but I only want to fetch the package count from rpm for performance reasons.

                                          carter@fedora
                                          -------------
             .',;::::;,'.                 OS: Fedora Linux 39 (Workstation Edition) x86_64
         .';:cccccccccccc:;,.             Host: Latitude 7400
      .;cccccccccccccccccccccc;.          Kernel: 6.7.4-200.fc39.x86_64
    .:cccccccccccccccccccccccccc:.        Uptime: 19 hours, 31 mins
  .;ccccccccccccc;.:dddl:.;ccccccc;.      Packages: 2525 (rpm), 48 (nix-user), 62 (flatpak-system), 13 (flatpak-user)
 .:ccccccccccccc;OWMKOOXMWd;ccccccc:.     Shell: bash 5.2.26
.:ccccccccccccc;KMMc;cc;xMMc;ccccccc:.    Display (AUO633D): 1920x1080 @ 60Hz [Built-in]
,cccccccccccccc;MMM.;cc;;WW:;cccccccc,    DE: Gnome 45.4
:cccccccccccccc;MMM.;cccccccccccccccc:    WM: Mutter (Wayland)
:ccccccc;oxOOOo;MMM000k.;cccccccccccc:    Icons: Papirus-Dark [GTK2/3/4]
cccccc;0MMKxdd:;MMMkddc.;cccccccccccc;    Terminal: GNOME Terminal 3.50.1
ccccc;XMO';cccc;MMM.;cccccccccccccccc'    Terminal Font: Monaco (15pt)
ccccc;MMo;ccccc;MMW.;ccccccccccccccc;     CPU: Intel(R) Core(TM) i7-8665U (8) @ 1.90 GHz
ccccc;0MNc.ccc.xMMd;ccccccccccccccc;      GPU: Intel UHD Graphics 620
cccccc;dNMWXXXWM0:;cccccccccccccc:,       Memory: 4.14 GiB / 15.43 GiB (27%)
cccccccc;.:odl:.;cccccccccccccc:,.        Disk (/): 86.13 GiB / 952.28 GiB (9%) - btrfs
ccccccccccccccccccccccccccccc:'.          Battery: 65% [Discharging]
:ccccccccccccccccccccccc:;,..    
 ':cccccccccccccccc::;,.                  ████████████████████████
                                          ████████████████████████

Wanted state:

Only the desired package managers are shown:

                                          carter@fedora
                                          -------------
             .',;::::;,'.                 OS: Fedora Linux 39 (Workstation Edition) x86_64
         .';:cccccccccccc:;,.             Host: Latitude 7400
      .;cccccccccccccccccccccc;.          Kernel: 6.7.4-200.fc39.x86_64
    .:cccccccccccccccccccccccccc:.        Uptime: 19 hours, 31 mins
  .;ccccccccccccc;.:dddl:.;ccccccc;.      Packages: 2525 (rpm)
 .:ccccccccccccc;OWMKOOXMWd;ccccccc:.     Shell: bash 5.2.26
.:ccccccccccccc;KMMc;cc;xMMc;ccccccc:.    Display (AUO633D): 1920x1080 @ 60Hz [Built-in]
,cccccccccccccc;MMM.;cc;;WW:;cccccccc,    DE: Gnome 45.4
:cccccccccccccc;MMM.;cccccccccccccccc:    WM: Mutter (Wayland)
:ccccccc;oxOOOo;MMM000k.;cccccccccccc:    Icons: Papirus-Dark [GTK2/3/4]
cccccc;0MMKxdd:;MMMkddc.;cccccccccccc;    Terminal: GNOME Terminal 3.50.1
ccccc;XMO';cccc;MMM.;cccccccccccccccc'    Terminal Font: Monaco (15pt)
ccccc;MMo;ccccc;MMW.;ccccccccccccccc;     CPU: Intel(R) Core(TM) i7-8665U (8) @ 1.90 GHz
ccccc;0MNc.ccc.xMMd;ccccccccccccccc;      GPU: Intel UHD Graphics 620
cccccc;dNMWXXXWM0:;cccccccccccccc:,       Memory: 4.14 GiB / 15.43 GiB (27%)
cccccccc;.:odl:.;cccccccccccccc:,.        Disk (/): 86.13 GiB / 952.28 GiB (9%) - btrfs
ccccccccccccccccccccccccccccc:'.          Battery: 65% [Discharging]
:ccccccccccccccccccccccc:;,..    
 ':cccccccccccccccc::;,.                  ████████████████████████
                                          ████████████████████████

Why the change is sensible:

The user should be able to configure which package managers get queried, in case it takes too long to fetch all packages with a bunch of different managers.

If this is already supported my apologies, I skimmed through the configuration options and didn't see anything like this.

Thanks.