When displaying the repo home view, do not redirect to unit types that
can't be defaults (which, at the moment, are the external wiki and issue
tracker unit types).
If we'd redirect to those, that would mean that a repository with the
Code unit disabled, and an external issue tracker would immediately
redirect to the external issue tracker, making it harder to reach other,
non-external units of the repo.
Fixes#1965.
Signed-off-by: Gergely Nagy <forgejo@gergo.csillger.hu>
(cherry picked from commit 44078e546022e25f5c805ef047fbc3b7c6075ec0)
(cherry picked from commit 1868dec2e4c2ba8e6807336e6dabd83e6138bcac)
(cherry picked from commit c3a8e9887092c8c089462a1cdb22a404aa11beb6)
(cherry picked from commit 9266b1916f1577075b0bf2ff14c7412cbd7cae43)
(cherry picked from commit 8fa5ff65af91c33df692a52457fe65e71c4bc3c1)
92f41d11dd