Fix stream in KernelContext in convolution and laplacian tests.

Signed-off-by: Michał Zientkiewicz <mzient@gmail.com>

Author: mzient

dali/kernels/imgproc/convolution/convolution_gpu_test.cu

@@ -158,6 +158,7 @@ struct ConvolutionGpuKernelTest : public ::testing::Test {
 
   void RunTest() {
     KernelContext ctx_cpu, ctx_gpu;
+    ctx_gpu.gpu.stream = 0;
     KernelCpu kernel_cpu;
     KernelGpu kernel_gpu;
 

dali/kernels/imgproc/convolution/laplacian_gpu_test.cu

@@ -161,6 +161,7 @@ struct LaplacianGpuTest : public ::testing::Test {
 
   void RunTest() {
     KernelContext ctx_cpu = {}, ctx_gpu = {};
+    ctx_gpu.gpu.stream = 0;
     KernelCpu kernel_cpu;
     KernelGpu kernel_gpu;
     int nsamples = in_.shape.size();