update workflows

.github/workflows/appimage.yml

@@ -4,7 +4,7 @@ on:
   push:
     branches: [ "main", "release-**"]
   pull_request:
-    branches: [ "main" ]
+    branches: [ "main", "headless-mode" ]
 
 jobs:
   build-appimage:
@@ -24,7 +24,7 @@ jobs:
         run: |
           sudo apt-get update
           sudo apt-get install -y build-essential libglfw3-dev libglfw3 libglew-dev \
-            libglm-dev libpng-dev libopenal-dev libluajit-5.1-dev libvorbis-dev libcurl4-openssl-dev libgtest-dev cmake squashfs-tools tree
+            libglm-dev libpng-dev libopenal-dev libluajit-5.1-dev libvorbis-dev libcurl4-openssl-dev libgtest-dev cmake squashfs-tools
           # fix luajit paths
           sudo ln -s /usr/lib/x86_64-linux-gnu/libluajit-5.1.a /usr/lib/x86_64-linux-gnu/liblua5.1.a
           sudo ln -s /usr/include/luajit-2.1 /usr/include/lua