add functional contribution section to CONTRIB.md
add functional contribution section to CONTRIB.md

lanwen/github-plugin,OpenDataSpace/github-plugin,lanwen/github-plugin,ouaibsky/github-plugin,jurajseffer/github-plugin,OpenDataSpace/github-plugin,javierarrieta/github-plugin,jurajseffer/github-plugin,jenkinsci/github-plugin,jenkinsci/github-plugin,lanwen/github-plugin,recena/github-plugin,fbelzunc/github-plugin,ouaibsky/github-plugin,recena/github-plugin,fbelzunc/github-plugin,fbelzunc/github-plugin,ouaibsky/github-plugin,OpenDataSpace/github-plugin,javierarrieta/github-plugin,Overseas-Student-Living/github-plugin,Overseas-Student-Living/github-plugin,recena/github-plugin,jenkinsci/github-plugin