VSCode: local schema doesn't work + weird caching issues

**Intended outcome:**

- I wanna use apollo tooling to write queries within my typescript files
- local schema is used created by fetching schema from server via apollo cli
`apollo service:download --endpoint=http://localhost:8000/graphql schema-twisto.json`

**Actual outcome:**

1. getting weird errors ( looks like vscode plugin does some weird caching )


If I change the path to non existent and back, plugin will get stuck on the same error:


2. If I explicitly reload code and reload the schema, errors are gone but, another one occurs ( **config is loaded 3 times** )


3. plugin doesn't work and still uses the old schema


**How to reproduce the issue:**

**Versions**
apollo vscode plugin: 1.5.2

Start by reproducing the issue with the Apollo VSCode plugin 1.5.2 and the locally downloaded schema from the documented apollo service:download command. Investigate the schema reload and caching behavior shown in the supplied recordings; done means the local schema is used after updates, errors do not persist, and the config is loaded once.

Written by the indexing model from the issue text.