Remove debugger from staging

jupyterlab/staging/package.json

@@ -25,7 +25,6 @@
     "@jupyterlab/console-extension": "~3.0.0-alpha.4",
     "@jupyterlab/coreutils": "~5.0.0-alpha.4",
     "@jupyterlab/csvviewer-extension": "~3.0.0-alpha.4",
-    "@jupyterlab/debugger-extension": "~3.0.0-alpha.4",
     "@jupyterlab/docmanager-extension": "~3.0.0-alpha.4",
     "@jupyterlab/documentsearch-extension": "~3.0.0-alpha.4",
     "@jupyterlab/extensionmanager-extension": "~3.0.0-alpha.4",
@@ -107,8 +106,6 @@
     "@jupyterlab/coreutils": "~5.0.0-alpha.4",
     "@jupyterlab/csvviewer": "~3.0.0-alpha.4",
     "@jupyterlab/csvviewer-extension": "~3.0.0-alpha.4",
-    "@jupyterlab/debugger": "~3.0.0-alpha.4",
-    "@jupyterlab/debugger-extension": "~3.0.0-alpha.4",
     "@jupyterlab/docmanager": "~3.0.0-alpha.4",
     "@jupyterlab/docmanager-extension": "~3.0.0-alpha.4",
     "@jupyterlab/docregistry": "~3.0.0-alpha.4",
@@ -205,7 +202,6 @@
       "@jupyterlab/completer-extension": "",
       "@jupyterlab/console-extension": "",
       "@jupyterlab/csvviewer-extension": "",
-      "@jupyterlab/debugger-extension": "",
       "@jupyterlab/docmanager-extension": "",
       "@jupyterlab/documentsearch-extension": "",
       "@jupyterlab/extensionmanager-extension": "",
@@ -250,7 +246,6 @@
       "@jupyterlab/apputils",
       "@jupyterlab/console",
       "@jupyterlab/coreutils",
-      "@jupyterlab/debugger",
       "@jupyterlab/docmanager",
       "@jupyterlab/extensionmanager",
       "@jupyterlab/filebrowser",