Updated user guide for stampede2

[qzhu2017]

@Kalharap @daniloarturo
Please update the following document regarding the use of stampede2.
https://github.com/MaterSim/CMS/wiki/Stampede2-User-Guide-%282022-under-ACCESS%29/_edit

[daniloarturo]

@qzhu2017 Thank you, Qiang. I have attached a link where we can find the user's guide of stampede2 https://portal.tacc.utexas.edu/user-guides/stampede2 to begin updating the document required.