Use format.sh in appveyor

.travis.yml

@@ -1,18 +0,0 @@
-dist: bionic
-
-stages:
-  - build
-
-matrix:
-  include:
-    - name: Static checks (format.sh)
-      stage: build
-      os: linux
-      addons:
-        apt:
-          packages:
-            - dos2unix
-            - recode
-
-script:
-  - bash ./format.sh

appveyor.yml

@@ -1,12 +1,21 @@
+---
+
 image: 
-  - Visual Studio 2019
-  - Ubuntu
   - macos
+  - Ubuntu2004
+  - Visual Studio 2019
 
 configuration: Release
 
 environment:
   APPVEYOR_YML_DISABLE_PS_LINUX: true
+
+install:
+- sh: |
+    if [ "$(uname)" != "Darwin" ]; then
+      sudo apt-get update -y
+      sudo apt-get install -y dos2unix recode
+    fi
     
 build_script:
   - ps: |
@@ -24,7 +33,16 @@ build_script:
       cmake --build . --config ${CONFIGURATION}
       cd ../
 
+test_script:
+  - sh: |
+      if [ "$(uname)" != "Darwin" ]; then
+        bash ./format.sh
+      fi
+
 artifacts:
-  - path: bin\$(configuration)\basisu.exe
+  # Linux
   - path: bin/basisu
+  # MacOS
   - path: bin_osx/basisu
+  # Windows
+  - path: bin\$(configuration)\basisu.exe