Fix tests for Barracuda (#2333)

* Removed obsolete 'TestDstWrongShape' test as it does not reflect how Barracuda tensors work

* Added proper test cleanup, to avoid warning messages from finalizer thread.

UnitySDK/Assets/ML-Agents/Editor/Tests/EditModeTestInternalBrainTensorApplier.cs

         public void Contruction()
         {
             var bp = new BrainParameters();
-            var tensorGenerator = new TensorApplier(bp, 0, new TensorCachingAllocator());
+            var alloc = new TensorCachingAllocator();
+            var tensorGenerator = new TensorApplier(bp, 0, alloc);
+            alloc.Dispose();
         }
 
         [Test]
                                                                 4f, 5f, 6f, 7f, 8f})
             };
             var agentInfos = GetFakeAgentInfos();
-            
-            var applier = new DiscreteActionOutputApplier(new int[]{2, 3}, 0, new TensorCachingAllocator());
+            var alloc = new TensorCachingAllocator();
+            var applier = new DiscreteActionOutputApplier(new int[]{2, 3}, 0, alloc);
             applier.Apply(inputTensor, agentInfos);
             var agents = agentInfos.Keys.ToList();
             var agent = agents[0] as TestAgent;
             action = agent.GetAction();
             Assert.AreEqual(action.vectorActions[0], 1);
             Assert.AreEqual(action.vectorActions[1], 2);
+            alloc.Dispose();
         }
         
         [Test]

UnitySDK/Assets/ML-Agents/Editor/Tests/EditModeTestInternalBrainTensorGenerator.cs

         public void Contruction()
         {
             var bp = new BrainParameters();
-            var tensorGenerator = new TensorGenerator(bp, 0, new TensorCachingAllocator());
+            var alloc = new TensorCachingAllocator();
+            var tensorGenerator = new TensorGenerator(bp, 0, alloc);
+            alloc.Dispose();
         }
 
         [Test]
+            var alloc = new TensorCachingAllocator();
-            var generator = new BatchSizeGenerator(new TensorCachingAllocator());
+            var generator = new BatchSizeGenerator(alloc);
+            alloc.Dispose();
         }
         
         [Test]
+            var alloc = new TensorCachingAllocator();
-            var generator = new SequenceLengthGenerator(new TensorCachingAllocator());
+            var generator = new SequenceLengthGenerator(alloc);
+            alloc.Dispose();
         }
         
         [Test]
             };
             var batchSize = 4;
             var agentInfos = GetFakeAgentInfos();
-            
-            var generator = new VectorObservationGenerator(new TensorCachingAllocator());
+            var alloc = new TensorCachingAllocator();
+            var generator = new VectorObservationGenerator(alloc);
             generator.Generate(inputTensor, batchSize, agentInfos);
             Assert.IsNotNull(inputTensor.Data);
             Assert.AreEqual(inputTensor.Data[0, 0], 1);
+            alloc.Dispose();
         }
         
         [Test]
             };
             var batchSize = 4;
             var agentInfos = GetFakeAgentInfos();
-            
-            var generator = new RecurrentInputGenerator(new TensorCachingAllocator());
+            var alloc = new TensorCachingAllocator();
+            var generator = new RecurrentInputGenerator(alloc);
             generator.Generate(inputTensor, batchSize, agentInfos);
             Assert.IsNotNull(inputTensor.Data);
             Assert.AreEqual(inputTensor.Data[0, 0], 0);
+            alloc.Dispose();
         }
         
         [Test]
             };
             var batchSize = 4;
             var agentInfos = GetFakeAgentInfos();
-
-            var generator = new PreviousActionInputGenerator(new TensorCachingAllocator());
+            var alloc = new TensorCachingAllocator();
+            var generator = new PreviousActionInputGenerator(alloc);
 
             generator.Generate(inputTensor, batchSize, agentInfos);
             Assert.IsNotNull(inputTensor.Data);
             Assert.AreEqual(inputTensor.Data[1, 1], 4);
+            alloc.Dispose();
         }
         
         [Test]
             };
             var batchSize = 4;
             var agentInfos = GetFakeAgentInfos();
-  
-            var generator = new ActionMaskInputGenerator(new TensorCachingAllocator());
+            var alloc = new TensorCachingAllocator();
+            var generator = new ActionMaskInputGenerator(alloc);
             generator.Generate(inputTensor, batchSize, agentInfos);
             Assert.IsNotNull(inputTensor.Data);
             Assert.AreEqual(inputTensor.Data[0, 0], 1);
+            alloc.Dispose();
         }
     }
 }

UnitySDK/Assets/ML-Agents/Editor/Tests/MultinomialTest.cs

         }
         
         [Test]
-        public void TestDstWrongShape()
-        {
-            Multinomial m = new Multinomial(2018);
-            
-            TensorProxy src = new TensorProxy
-            {
-                ValueType = TensorProxy.TensorType.FloatingPoint,
-                Data = new Tensor(0,1)
-            };
-            TensorProxy dst = new TensorProxy
-            {
-                ValueType = TensorProxy.TensorType.FloatingPoint,
-                Data = new Tensor(0,2)
-            };
-
-            Assert.Throws<ArgumentException>(() => m.Eval(src, dst));
-        }
-
-        [Test]
         public void TestUnequalBatchSize()
         {
             Multinomial m = new Multinomial(2018);