GraphQL API Search result line numbers

Created by: aisbaa

• Sourcegraph version: 3.12.7

Steps to reproduce:

1. Run this search graphql query

Expected behavior:

Matched result lines are off by 1, seems like API file starts from line 0.

Actual behavior:

Expect file to start from line 1 or mention that it starts from 0 in the docs.

https://github.com/sourcegraph/sourcegraph/blob/94e5aa4c6dc58fe46c8febc00a081b26cf65a7c1/cmd/frontend/graphqlbackend/schema.graphql#L2906