temp: add runs to dockerfile to troubleshoot envvar (#30200)

Dockerfile

@@ -123,7 +123,9 @@ RUN pip install -r requirements/edx/base.txt
 FROM base as lms-docker
 ENV SERVICE_VARIANT lms
 ARG LMS_CFG
+RUN echo "$LMS_CFG"
 ENV LMS_CFG="$LMS_CFG"
+RUN echo "$LMS_CFG"
 ENV EDX_PLATFORM_SETTINGS='docker-production'
 ENV DJANGO_SETTINGS_MODULE="lms.envs.$EDX_PLATFORM_SETTINGS"
 EXPOSE 8000