fix: adjust enterprise api url for graphql use case

[Anonycoders]

Description

For GitHub.com this is https://api.github.com/graphql. For GitHub Enterprise Server, the GraphQL endpoint is at /api/graphql (not /api/v3/graphql).
This change makes sure the URL constructed appropriately.

https://docs.github.com/en/enterprise-cloud@latest/graphql/guides/managing-enterprise-accounts#3-setting-up-insomnia-to-use-the-github-graphql-api-with-enterprise-accounts

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 85.03%. Comparing base (c57be3c) to head (312f16a).

Additional details and impacted files

@@            Coverage Diff            @@
##               main    #2180   +/-   ##
=========================================
  Coverage     85.02%   85.03%           
  Complexity     2496     2496           
=========================================
  Files           237      237           
  Lines          7354     7355    +1     
  Branches        388      388           
=========================================
+ Hits           6253     6254    +1     
  Misses          871      871           
  Partials        230      230           

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[bitwiseman]

This changed behavior isn't really tested by any existing test. Because of how it is written, code coverage doesn't catch it. On the plus side, we know this doesn't break the GitHub.com scenario, but we don't have any verification of the enterprise scenario.

Please add a test to the enterprise github tests that calls createGraphQLRequest and verifies the Requester has the new expected /api/graphql URL. You don't have actually make the http call, just check the value.

[bitwiseman]

Add a test that exercises the new behavior. Thanks for contributing!