[Jasper/PyT][QuartzNet/PyT] remove pyyaml requirement, as a newer version is inside the container

PyTorch/SpeechRecognition/Jasper/Dockerfile

@@ -21,7 +21,7 @@ WORKDIR /workspace/jasper
 
 # Install requirements (do this first for better caching)
 COPY requirements.txt .
-RUN conda install -y pyyaml==5.4.1
+RUN if [[ ! -z "$(command -v conda)" ]]; then conda install -y pyyaml==5.4.1; fi
 RUN pip install --disable-pip-version-check -U -r requirements.txt
 
 RUN pip install --force-reinstall --extra-index-url https://developer.download.nvidia.com/compute/redist nvidia-dali-cuda110==1.2.0

PyTorch/SpeechRecognition/QuartzNet/Dockerfile

@@ -21,7 +21,7 @@ WORKDIR /workspace/quartznet
 
 # Install requirements (do this first for better caching)
 COPY requirements.txt .
-RUN conda install -y pyyaml==5.4.1
+RUN if [[ ! -z "$(command -v conda)" ]]; then conda install -y pyyaml==5.4.1; fi
 RUN pip install --disable-pip-version-check -U -r requirements.txt
 
 RUN pip install --extra-index-url https://developer.download.nvidia.com/compute/redist nvidia-dali-cuda110==1.2.0