fix(ci): do not install packages at pacman-git CI level (#1860)

* fix(ci): do not attempt to install extra packages for building pacman-git

* install needed in ci image

* fix missing pacman key

* wip

* add missing deps

.github/workflows/testing-git.yml

@@ -24,12 +24,10 @@ jobs:
             ${{ runner.os }}-go-
       - name: checkout pacman-git
         run: |
-          pacman -Sy --overwrite=* --noconfirm archlinux-keyring
-          pacman -Su --overwrite=* --noconfirm sudo base-devel
           git clone https://aur.archlinux.org/pacman-git
           useradd github
-          chmod -R 777 pacman-git
           echo 'github ALL=(ALL) NOPASSWD: ALL' >> /etc/sudoers
+          chmod -R 777 pacman-git
           su github -c 'cd pacman-git; yes | makepkg -si --nocheck'
       - name: Run Build and Tests with pacman-git
         run: make test