Fix a harmless bug in the `diagrams` tool that results in some duplicated data in the generated `.dot` files
Fix a harmless bug in the `diagrams` tool that results in some duplicated data in the generated `.dot` files

LogtalkDotOrg/logtalk3,LogtalkDotOrg/logtalk3,LogtalkDotOrg/logtalk3,LogtalkDotOrg/logtalk3,LogtalkDotOrg/logtalk3,LogtalkDotOrg/logtalk3,LogtalkDotOrg/logtalk3