MCR-3835: Attach lambda authorizer to api gateway endpoint

[pearl-truss]

Summary

New graphql_external endpoint created. This is a copy of the graphql endpoint with the following changes:

• Only has a get method. I believe we said we would limit 3rd parties to queries for now. I added in the post method because of the language in https://qmacbis.atlassian.net/browse/MCR-3836 seems like it's something we will eventually implement
• URL path to invoke is v1/graphql/external per eng notes on the ticket
• 3rd party authorizer is attached

Related issues

https://qmacbis.atlassian.net/browse/MCR-3835

QA guidance

I tested locally with curl

curl \
  --request GET \
  --header "Accept: text/javascript" \
  --header "Authorization: Bearer {token}" \
  --data '{"query": "query { indexHealthPlanPackage { totalCount edges{} } }"}' \
http://127.0.0.1:3030/local/v1/graphql/external

With a valid token an apollo error is returned

Context creation failed: Log: placing user in gql context failed"," at ApolloServer.context.

I believe this error will resolve after https://qmacbis.atlassian.net/browse/MCR-3836 is completed

With an invalid token a permission error is returned

"error":"Forbidden","message":"No principalId set on the Response"

[macrael]

I didn't think about this when doing the separate jwthealth lambda, but if we can just add these as separate events using a different authorizer to our existing lambda rather than having to clone the whole lambda that would be nice

[macrael]

Could these events be inside the regular graphql lambda or do they need to be their own lambda?

[pearl-truss]

I confirmed it works with combining with the regular graphql lambda. I think this falls under "lambda proxy integration" which is the default used with serverless