minor: remove some recent mono compiler warnings

OpenSim/Data/Tests/RegionTests.cs

@@ -1069,8 +1069,6 @@ namespace OpenSim.Data.Tests
             regionInfo.RegionLocX = 0;
             regionInfo.RegionLocY = 0;
 
-            Scene scene = new Scene(regionInfo);
-
             SceneObjectPart sop = new SceneObjectPart();
             sop.Name = name;
             sop.Description = name;

OpenSim/Region/ScriptEngine/Shared/Tests/OSSL_ApiAttachmentTests.cs

@@ -158,7 +158,7 @@ namespace OpenSim.Region.ScriptEngine.Shared.Tests
             {
                 osslApi.osForceAttachToAvatarFromInventory(taskInvObjItemName, (int)attachPoint);
             }
-            catch (Exception e)
+            catch (Exception)
             {
                 exceptionCaught = true;
             }