[SDK] Fix empty list for env variables and numpy version

examples/v1beta1/trial-images/darts-cnn-cifar10/Dockerfile.cpu

@@ -4,10 +4,12 @@ ENV TARGET_DIR /opt/darts-cnn-cifar10
 
 ADD examples/v1beta1/trial-images/darts-cnn-cifar10 ${TARGET_DIR}
 
-WORKDIR  ${TARGET_DIR}
+WORKDIR ${TARGET_DIR}
 
+# TODO (andreyvelich): This is required since torchvision==0.17.1 is incompatible with numpy 2.0
+RUN pip install numpy==1.26.0
 RUN pip install --prefer-binary --no-cache-dir torch==2.2.1 torchvision==0.17.1
-RUN pip install --prefer-binary --no-cache-dir -r requirements.txt
+
 RUN chgrp -R 0 ${TARGET_DIR} \
   && chmod -R g+rwX ${TARGET_DIR}
 

examples/v1beta1/trial-images/pytorch-mnist/Dockerfile.cpu

@@ -6,6 +6,9 @@ WORKDIR /opt/pytorch-mnist
 
 # Add folder for the logs.
 RUN mkdir /katib
+
+# TODO (andreyvelich): This is required since torchvision==0.17.1 is incompatible with numpy 2.0
+RUN pip install numpy==1.26.0
 RUN pip install --prefer-binary --no-cache-dir torch==2.2.1 torchvision==0.17.1
 RUN pip install --prefer-binary --no-cache-dir -r requirements.txt
 

examples/v1beta1/trial-images/pytorch-mnist/requirements.txt

@@ -1,2 +1 @@
 cloudml-hypertune==0.1.0.dev6
-Pillow>=9.1.1

sdk/python/v1beta1/kubeflow/katib/api/katib_client.py

@@ -386,8 +386,8 @@ def tune(
                                 image=base_image,
                                 command=["bash", "-c"],
                                 args=[exec_script],
-                                env=env,
-                                env_from=env_from,
+                                env=env if env else None,
+                                env_from=env_from if env_from else None,
                                 resources=resources_per_trial,
                             )
                         ],