ci/action/arch: Switch from absolute Arch docker version to a more relaxed one (#966)

.github/workflows/aur-prerelease.yml

@@ -7,7 +7,7 @@ on:
 jobs:
   aur-pre-release:
     runs-on: ubuntu-20.04
-    container: archlinux:base-20210228.0.16308
+    container: archlinux:base
     steps:
       - name: Checkout Project
         uses: actions/checkout@v1

.github/workflows/aur-release.yml

@@ -7,7 +7,7 @@ on:
 jobs:
   aur-release:
     runs-on: ubuntu-20.04
-    container: archlinux:base-20210228.0.16308
+    container: archlinux:base
     steps:
       - name: Checkout Project
         uses: actions/checkout@v1

deploy-aur.sh

@@ -3,7 +3,7 @@
 set -e
 
 # Setup base system
-pacman -Syu --noconfirm openssh git gettext binutils
+pacman -Syu --noconfirm openssh git gettext binutils archlinux-keyring
 sed -i "s/INTEGRITY_CHECK=.*$/INTEGRITY_CHECK=(sha256)/" /etc/makepkg.conf
 useradd -ms /bin/bash aur
 su -m aur <<'EOSU'