Supporting newer Apollo versions (4 and above)

### Add support for newer Apollo version (version 4 and above)
After moving from `apollo-server` to `@apollo/server`, the makeSchemaAndPlugin starts reporting following issue:
```
Error occurred creating context!
TypeError: Cannot convert undefined or null to object
```

After some debugging, it seems that issue is coming from this piece of code from the makeSchemaAndPlugin function:
```
async didResolveOperation(requestContext) {
const {
context: graphqlContext,
request: graphqlRequest
} = requestContext;
```

`requestContext` no longer has `context` property in it.
` requestContext.context` property is now called ` requestContext.contextValue`

Is this package planned to be updated to support the latest Apollo version?