logging(gitstart) tracking issue: migrate graphqlbackend to use sourcegraph/log

Created by: bobheadxi

Problem statement

The graphqlbackend layer in Sourcegraph's frontend service has a lot of log15 usage. As a core entrypoint to many parts of Sourcegraph, having this layer migrated could help speed adoption of the new logging library.

Success criteria

All 85 usages of log15 in cmd/frontend/graphqlbackend are replaced with usages of appropriately scoped loggers.

https://sourcegraph.com/search?q=context:global+repo:%5Egithub%5C.com/sourcegraph/sourcegraph%24+file:%5Ecmd/frontend/graphqlbackend+log15&patternType=literal

Implementation details

Most usages here fall in one of two places:

1. a resolver struct function
2. a helper function

In case 1, the resolver struct should hold a reference to a log.Logger. In case 2, the helper should accept a logger parameter.

Tracked issues

@gitstart-sourcegraph: 1.50d

• https://github.com/sourcegraph/sourcegraph/issues/37586 1.50d
  • (🏁 40 days ago) https://github.com/sourcegraph/sourcegraph/issues/37398 1.00d
  • (🏁 65 days ago) https://github.com/sourcegraph/sourcegraph/issues/37399 0.50d

Completed: 1.50d

• (🏁 63 days ago) https://github.com/sourcegraph/sourcegraph/issues/33192 1.50d 🛠️