Fix vb comment start line and end line regex
Fix vb comment start line and end line regex

sergey-vershinin/docfx,superyyrrzz/docfx,928PJY/docfx,pascalberger/docfx,928PJY/docfx,superyyrrzz/docfx,pascalberger/docfx,LordZoltan/docfx,dotnet/docfx,superyyrrzz/docfx,928PJY/docfx,sergey-vershinin/docfx,hellosnow/docfx,LordZoltan/docfx,hellosnow/docfx,pascalberger/docfx,dotnet/docfx,sergey-vershinin/docfx,LordZoltan/docfx,dotnet/docfx,hellosnow/docfx,DuncanmaMSFT/docfx,LordZoltan/docfx,DuncanmaMSFT/docfx