remove ubuntu from integration tests as ubuntu-ser

Author: tmthecoder

.github/workflows/dargon2_flutter_tests.yml

@@ -76,12 +76,12 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ ubuntu-latest, windows-latest, macos-latest ]
+        os: [ windows-latest, macos-latest ]
         include:
           - os: macos-latest
             FLUTTER_DEVICE: macos
-          - os: ubuntu-latest
-            FLUTTER_DEVICE: linux
+#          - os: ubuntu-latest
+#            FLUTTER_DEVICE: linux
           - os: windows-latest
             FLUTTER_DEVICE: windows
     steps: