Prevent user from entering incorrect characters in Live Notifications channels list (#3715)

Co-authored-by: Sidd <iProdigy@users.noreply.github.com>
Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

src/widgets/helper/EditableModelView.cpp

@@ -1,4 +1,5 @@
 #include "EditableModelView.hpp"
+#include "widgets/helper/RegExpItemDelegate.hpp"
 
 #include <QAbstractItemView>
 #include <QAbstractTableModel>
@@ -90,6 +91,10 @@ EditableModelView::EditableModelView(QAbstractTableModel *model, bool movable)
     // finish button layout
     buttons->addStretch(1);
 }
+void EditableModelView::setValidationRegexp(QRegularExpression regexp)
+{
+    this->tableView_->setItemDelegate(new RegExpItemDelegate(this, regexp));
+}
 
 void EditableModelView::setTitles(std::initializer_list<QString> titles)
 {