updated structure

doc/source/cicd.rst

-Continuous Integration
-======================
+Build and test
+==============
 
 The Continuous Integration is based on Jenkins.
 A push to git repository will trigger a build for the package on Jenkins platform.
@@ -116,13 +116,16 @@ The Numpy style docstring check is only for the packages listed below.
 We welcome other packages participate in.
 
 
+Continuous integration
+======================
+
 Using ``Jenkins``
 -----------------
 
 ... how to use jenkins
 
 
-Docker
-------
+Using ``docker``
+----------------
 
 to be updated