chore(general): add SortFilterProxyModel submodule

It's necessary as a result of StatusQ merge

.gitmodules

@@ -118,3 +118,6 @@
 [submodule "vendor/status-keycard-go"]
 	path = vendor/status-keycard-go
 	url = https://github.com/status-im/status-keycard-go.git
+[submodule "vendor/SortFilterProxyModel"]
+	path = ui/StatusQ/vendor/SortFilterProxyModel
+	url = https://github.com/status-im/SortFilterProxyModel.git

ui/StatusQ/.gitignore

@@ -1,19 +0,0 @@
-.DS_Store
-moc_*
-*.pro.user
-qrc_*
-*.o
-build-*
-*.qmlc
-bin
-*.app
-*.autosave
-Makefile
-.qmake.stash
-*_qml.cpp
-*_qmlcache.qrc
-sandbox/qmlcache_loader.cpp
-doc/html
-CMakeLists.txt.user
-.vscode
-build/