Takashi Kajinami 30a8ae7e48 Remove reference to tempest-horizon repo
... because the repo has been retired[1].

[1] 7b03c9dfb97e9900abd5fc0f5e9112dce7c59a0d

Closes-Bug: #1915832
Change-Id: I96760e4e4f35b3f044ba03156a0fa449a9854b5b
2021-02-16 14:50:04 +00:00
..