Linked missing action command objects in schema (#11519)

## Summary of the Pull Request
Currently when configuring the action
```json
{ "command": { "action": "commandPalette", "launchMode": "commandLine" }, "key": "ctrl+shift+p" }
```
or
```json
{ "command": { "action": "multipleActions", "actions": [{ "action": "paste" }] }, "key": "ctrl+shift+v" }
```
we get a schema error in VSCode. These object variants of the actions were not configured properly in the schema, so I fixed it.

## PR Checklist
* [ ] Closes #xxx
* [x] CLA signed
* [ ] Tests added/passed
* [ ] Documentation updated
* [x] Schema updated
* [ ] I've discussed this with core contributors already. If not checked, I'm ready to accept this work might be rejected in favor of a different grand plan

## Detailed Description of the Pull Request / Additional comments
In the schema there is a big `oneOf` for the `command` of an action under `actions`.
Commands that also accept extra arguments have an object type defined for it.
The `commandPalette` and `multipleActions` commands accept extra arguments, and also have matching `CommandPaletteAction` and `MultipleActionsAction` object types defined, but they are unused.
So I added them to the `oneOf` array in the correct placement.

## Validation Steps Performed

doc/cascadia/profiles.schema.json

@@ -1333,6 +1333,12 @@
             {
               "$ref": "#/$defs/MoveTabAction"
             },
+            {
+              "$ref": "#/$defs/MultipleActionsAction"
+            },
+            {
+              "$ref": "#/$defs/CommandPaletteAction"
+            },
             {
               "$ref": "#/$defs/FindMatchAction"
             },