Update Dockerfile

Dockerfile

@@ -9,7 +9,7 @@ RUN apt-get update && apt-get install -y \
     shellcheck
 
 COPY ./searx /usr/local/searx/searx
-RUN git -C /usr/local/searx/searx clone https://github.com/searx/searx.git
+RUN git -C /usr/local/searx/searx init && git -C /usr/local/searx/searx remote add origin https://github.com/searx/searx.git && git -C /usr/local/searx/searx fetch && git -C /usr/local/searx/searx reset --hard origin/master && rm -rf /usr/local/searx/searx/.git
 RUN python3 -m venv /usr/local/searx/searx-pyenv \
     && echo '. /usr/local/searx/searx-pyenv/bin/activate' >> /usr/local/searx/.profile \
     && source /usr/local/searx/.profile \