bug#49458: kicad-doc build failure: YAML/Tiny.pm module loading

[Christopher Howard]

kicad-doc fails to build with this error:

```
po4a::chooser: Module loading error: Can't locate YAML/Tiny.pm in @INC
(you may need to install the YAML::Tiny module)
```

christopher@theoden ~$ neofetch --stdout
christopher@theoden 
------------------- 
OS: Guix System 02562e2f1e1b0fcc4ae17a54885f67b38fc1be46 x86_64 
Host: OptiPlex 9020 00 
Kernel: 5.12.13-gnu 
Uptime: 1 hour, 52 mins 
Packages: 94 (guix-system), 109 (guix-user) 
Shell: bash 5.0.16 
Resolution: 1920x1080 
DE: GNOME 
Theme: Adwaita [GTK2/3] 
Icons: Adwaita [GTK2/3] 
Terminal: kitty 
CPU: Intel i5-4570 (4) @ 3.600GHz 
GPU: Intel HD Graphics 
GPU: AMD ATI Radeon HD 8490 / R5 235X OEM 
Memory: 2763MiB / 7869MiB

-- 
Christopher Howard
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