Fix validation of adlist url

Already existing regex validation will be used on url after removing @ (in case
its in separating userinfo and host).

Signed-off-by: Matej Dujava <mdujava@kocurkovo.cz>
Fixes: https://github.com/pi-hole/pi-hole/issues/3911
Fixes: 7d19ee1b: validate blocklist URL before adding to the database (#3237)

advanced/Scripts/webpage.sh

@@ -486,10 +486,15 @@ SetWebUITheme() {
 }
 
 CheckUrl(){
-    local regex
+    local regex check_url
     # Check for characters NOT allowed in URLs
-    regex="[^a-zA-Z0-9:/?&%=~._-]"
-    if [[ "${1}" =~ ${regex} ]]; then
+    regex="[^a-zA-Z0-9:/?&%=~._()-;]"
+
+    # this will remove first @ that is after schema and before domain
+    # \1 is optional schema, \2 is userinfo
+    check_url="$( sed -re 's#([^:/]*://)?([^/]+)@#\1\2#' <<< "$1" )"
+
+    if [[ "${check_url}" =~ ${regex} ]]; then
         return 1
     else
         return 0