Disable indexing swift packages in subfolders on this repo (#1704)

When developing in this repository if you have the Swift extension
installed sourcekit-lsp will begin indexing the test projects in
assets/test which can be disruptive when opening the project for the
first time.

Author: plemarquand

.vscode/settings.json

@@ -17,5 +17,6 @@
 
   // Disable for when opening files in this workspace
   "swift.disableAutoResolve": true,
-  "swift.autoGenerateLaunchConfigurations": false
+  "swift.autoGenerateLaunchConfigurations": false,
+  "swift.sourcekit-lsp.disable": true
 }