Add RAdam test

Author: vballoli

Tests/TensorFlowTests/SequentialTests.swift

@@ -42,6 +42,7 @@ final class SequentialTests: XCTestCase {
         let amsgrad = AMSGrad(for: model, learningRate: 0.02)
         let adagrad = AdaGrad(for: model, learningRate: 0.02)
         let adadelta = AdaDelta(for: model, learningRate: 0.02)
+        let radam = RAdam(for: model, learningRate: 0.02)
         let x: Tensor<Float> = [[0, 0], [0, 1], [1, 0], [1, 1]]
         let y: Tensor<Float> = [0, 1, 1, 0]
         Context.local.learningPhase = .training
@@ -58,6 +59,7 @@ final class SequentialTests: XCTestCase {
                 amsgrad.update(&model, along: 𝛁model)
                 adagrad.update(&model, along: 𝛁model)
                 adadelta.update(&model, along: 𝛁model)
+                radam.update(&model, along: 𝛁model)
             }
         }
         XCTAssertEqual(model.inferring(from: [[0, 0], [0, 1], [1, 0], [1, 1]]),