debug docker build

face_recognition/Dockerfile

@@ -1,6 +1,7 @@
 FROM python:3.6
 COPY ./requirements.txt /app/requirements.txt
 WORKDIR /app
+RUN pip install CMake
 RUN pip install -r requirements.txt
 RUN rm requirements.txt
 RUN useradd -ms /bin/bash admin

face_recognition/requirements.txt

@@ -1,3 +1,3 @@
-Flask
+≈Flask
 CMake
 face_recognition