Fix invalid chars pattern to allow numbers

insert-toc/info.json

@@ -4,7 +4,7 @@
   "script": "insert-toc.qml",
   "authors": ["@flopp", "@toindev"],
   "platforms": ["linux", "macos", "windows"],
-  "version": "0.0.2",
+  "version": "0.0.3",
   "minAppVersion": "17.06.2",
   "description" : "This script scans the current note for headlines, generates a table of contents, and inserts a the TOC into the note."
 }

insert-toc/insert-toc.qml

@@ -47,7 +47,7 @@ Script {
     function extractLink(title) {
         var lowercase = title.toLowerCase()
         var spaceReplaced = lowercase.replace(/ /g, "-")
-        var invalidCharsRemoved = spaceReplaced.replace(/[^A-Za-zÀ-ÿ-_]/g, "")
+        var invalidCharsRemoved = spaceReplaced.replace(/[^0-9A-Za-zÀ-ÿ-_]/g, "")
         return invalidCharsRemoved;
     }