`TypeError: Cannot read properties of undefined (reading 'name')`

Receiving this after the latest VSCode update. Anyone with the same error?

```
/.vscode/extensions/apollographql.vscode-apollo-1.19.9/lib/language-server/errors/validation.js:103
selectsClientFieldSet = Boolean(clientFields && clientFields.includes(fieldDef.name));
^

TypeError: Cannot read properties of undefined (reading 'name')
```

┆Issue is synchronized with this [Jira Task](https://apollographql.atlassian.net/browse/NEBULA-1075) by [Unito](https://www.unito.io)

Start by reproducing the error after the VSCode update and inspect lib/language-server/errors/validation.js around line 103, where fieldDef.name is accessed. Trace why fieldDef is undefined for the affected GraphQL input; done means validation no longer throws this TypeError for that case.

Written by the indexing model from the issue text.