[fluffychat] use own docker image

fluffychat.yml

@@ -7,22 +7,9 @@ platform:
   os: linux
   arch: amd64
 
-steps:
-- name: prepare
-  image: archlinux:base-devel
-  commands:
-  - pacman -Sy git java-environment glu unzip libglvnd python --noconfirm
-  - useradd builduser -m
-  - git clone https://aur.archlinux.org/flutter.git
-  - chown -R builduser:builduser flutter
-  - cd flutter && su builduser
-  - PKGEXT=".pkg.tar" makepkg 
-
 - name: build
-  image: archlinux:base-devel
+  image: garionion/archlinux-flutter
   commands:
-  - pacman -Sy clang cmake ninja git unzip gtk3 --noconfirm
-  - pacman -U flutter/flutter-*-x86_64.pkg.tar --noconfirm
   - sh scripts/build-linux.sh
 
 - name: bundle