Add ```puml rendering support in the md file (#397)
Add ```puml rendering support in the md file (#397)

Co-authored-by: haipengno1 <da8aef52494acf48499716412188e595bdfd33cc@gmail.com>
qjebbs/vscode-plantuml,qjebbs/vscode-plantuml,qjebbs/vscode-plantuml