docs: Add Manjaro/Arch dependencies on getting started page (#2701)

* Update getting_started_build_tools.md

* Update getting_started_build_tools.md

docs/getting_started_build_tools.md

@@ -42,6 +42,12 @@ Fedora / Red Hat example:
 
     sudo dnf install gcc unzip wget zip dfu-util dfu-programmer avr-gcc avr-libc binutils-avr32-linux-gnu arm-none-eabi-gcc-cs arm-none-eabi-binutils-cs arm-none-eabi-newlib
     
+Arch / Manjaro example:
+
+    pacman -S base-devel gcc unzip wget zip avr-gcc avr-binutils avr-libc dfu-util arm-none-eabi-gcc arm-none-eabi-binutils arm-none-eabi-newlib git
+
+(the `dfu-programmer` package is availble on AUR only so you should download from there or use an AUR helper)
+
 ## Nix
 
 If you're on [NixOS](https://nixos.org/), or have Nix installed on Linux or macOS, run `nix-shell` from the repository root to get a build environment.