extension slows down intellisense features

## Actual Behavior
When this extension is enabled intellisense features such as go-to-definition and hovering for type info are noticeably slower than usual, taking several seconds when they would normally be close to instantaneous. This includes for symbols that are not part of a GraphQl query such as TypeScript variables.

## Expected Behavior

## Steps to Reproduce the Problem Or Description

## Specifications

- GraphQL for VSCode Extension Version: 0.3.18
- VSCode Version: 1.61.1
- OS Name: Mac OS
- OS Version: 11.6

## Logs Of TS Server || GraphQL Language Service
```Starting inspector on localhost:6009 failed: address already in use
10/15/2021, 4:28:05 PM [4] (pid: 10297) graphql-language-service-usage-logs: {"type":"usage","messageType":"initialize"}
10/15/2021, 4:28:24 PM [4] (pid: 10297) graphql-language-service-usage-logs: {"type":"usage","messageType":"textDocument/didOpen","projectName":"default","fileName":"file:///Users/nathanielpalmer/simplisafe/projects/ss-ecomm-frontend/src/templates/PartnerPage.tsx"}
10/15/2021, 4:31:50 PM [4] (pid: 10297) graphql-language-service-usage-logs: {"type":"usage","messageType":"textDocument/didOpen","projectName":"default","fileName":"file:///Users/nathanielpalmer/simplisafe/projects/ss-ecomm-frontend/src/componentMappings.ts"}
[Error - 4:31:50 PM] Request textDocument/documentSymbol failed.
Message: Request textDocument/documentSymbol failed with message: A cached document cannot be found.
Code: -32603 ```