use GitHub instead of Github
minor #4004 use GitHub instead of Github (xabbuh)

This PR was merged into the 2.3 branch.

Discussion
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use GitHub instead of Github

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | no
| Applies to    | all
| Fixed tickets |

Commits
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60015e6 use GitHub instead of Github
Merge branch '2.3' into 2.4

* 2.3:
  use GitHub instead of Github
Merge branch '2.4' into 2.5

* 2.4:
  use GitHub instead of Github
Merge branch '2.5'

* 2.5:
  use GitHub instead of Github