temporarily make mono to run first

appveyor.yml

@@ -6,6 +6,10 @@ skip_branch_with_pr: true
 
 environment:
   matrix:
+    - target_framework: mono
+      is_32bit: False
+    - target_framework: mono
+      is_32bit: True
     - target_framework: netcoreapp2.0
       is_32bit: False
     #- target_framework: netcoreapp2.0 # As far as I understand, 32 bit test execution is not supported by "dotnet xunit"
@@ -22,10 +26,7 @@ environment:
       is_32bit: False
     - target_framework: net471
       is_32bit: True
-    - target_framework: mono
+    
-      is_32bit: False
-    - target_framework: mono
-      is_32bit: True
 
 install:
   - ps: |