Change PR-CI-PY3 cc version (#30771)

* fix cc version

* fix

* add readme in whl package

tools/dockerfile/build_scripts/build_utils.sh

@@ -130,6 +130,12 @@ function build_cpython {
 
 function build_cpythons {
     for py_ver in $@; do
+        if [ ${py_ver} == "2.7.15" ]; then
+            GET_PIP_URL="https://bootstrap.pypa.io/2.7/get-pip.py"
+        elif [ ${py_ver} == "3.5.1" ]  ;then
+            GET_PIP_URL="https://bootstrap.pypa.io/3.5/get-pip.py"
+        fi
+
         check_var $GET_PIP_URL
         curl -sLO $GET_PIP_URL
         build_cpython $py_ver

tools/dockerfile/ci_dockerfile.sh

@@ -41,6 +41,7 @@ function make_centos_dockerfile(){
   sed "s/<baseimg>/11.0-cudnn8-devel-centos7/g" Dockerfile.centos >${dockerfile_name}
   sed -i "s#COPY build_scripts /build_scripts#COPY tools/dockerfile/build_scripts  ./build_scripts#g" ${dockerfile_name} 
   dockerfile_line=$(wc -l ${dockerfile_name}|awk '{print $1}')
+  sed -i "${dockerfile_line}i RUN rm -f /usr/bin/cc && ln -s /usr/local/gcc-8.2/bin/gcc /usr/bin/cc" ${dockerfile_name}
   sed -i "${dockerfile_line}i RUN ln -s /usr/lib64/libz.so /usr/local/lib/libz.so \\
     RUN ln -s /usr/local/lib/libnccl.so /usr/local/cuda/lib64/ \\
     RUN rm -rf /usr/include/NvInfer*" ${dockerfile_name}