Installing in Dockerfile breaks Deepstream installation

[mfoglio]

I am installing this package using pip within a Dockerfile build:
RUN pip3 install git+https://github.com/jackersson/gstreamer-python.git#egg=gstreamer-python
The base image I am using is the Deepstream image nvcr.io/nvidia/deepstream:6.0.1-devel. If I do this, when I run the container, Deepstream plugins can't be found anymore (e.g. get-inspect-1.0 nvinfer can't find nvinfer). However, if I install this very library (in the same way) within the container (vs during the docker build) I have no issues and everything works fine: Deepstream plugins can be found.
Any hint on what could be causing this issue?