fix(memory leak): don't override default deconstructor + reset shared_ptr + ensure modal get's cleaned up

Signed-off-by: Rachel Powers <508861+Ryex@users.noreply.github.com>

launcher/ui/pages/modplatform/ResourcePage.cpp

@@ -83,6 +83,8 @@ ResourcePage::ResourcePage(ResourceDownloadDialog* parent, BaseInstance& base_in
 ResourcePage::~ResourcePage()
 {
     delete m_ui;
+    if (m_model)
+        delete m_model;
 }
 
 void ResourcePage::retranslate()