Cap get-pip.py version

Author: zhaoqin-github

f5-sdk-dist/Docker/redhat/7/Dockerfile

@@ -1,7 +1,7 @@
 FROM centos:7
 
 RUN yum update -y && yum install rpm-build make python-setuptools -y
-RUN curl "https://bootstrap.pypa.io/get-pip.py" -o "get-pip.py"
+RUN curl "https://bootstrap.pypa.io/pip/2.7/get-pip.py" -o "get-pip.py"
 RUN python get-pip.py
 
 COPY ./build-rpm.py /build-rpm.py