Links in markdown should be absolute to the repository not the server

Fix #15075

Signed-off-by: Andrew Thornton <[email protected]>

modules/markup/markdown/goldmark.go

@@ -7,6 +7,7 @@ package markdown
 import (
 	"bytes"
 	"fmt"
+	"path"
 	"regexp"
 	"strings"
 
@@ -99,6 +100,8 @@ func (g *ASTTransformer) Transform(node *ast.Document, reader text.Reader, pc pa
 				prefix = strings.Replace(prefix, "/src/", "/media/", 1)
 
 				lnk := string(link)
+				lnk = path.Clean("/" + lnk)[1:]
+
 				lnk = giteautil.URLJoin(prefix, lnk)
 				link = []byte(lnk)
 			}