Update devcontainer memory settings

CodeQL CLI needs a minimum of 2G of memory. By default, the memory used is slightly less than that, leading to poor performance.

This change also removes two old, unused settings.

Author: aeisenberg

.devcontainer/devcontainer.json

@@ -4,8 +4,7 @@
         "slevesque.vscode-zipexplorer"
     ],
     "settings": {
-        "codeQL.experimentalBqrsParsing": true,
-        "codeQL.experimentalFeatures": true,
+        "codeQL.runningQueries.memory": 2048,
         "codeQL.runningQueries.debug": true
     }
-}
+}