Allow higher amount of restarts for Pleroma.Repo during testing

This was done by floatingghost as part of a bigger commit in Akkoma.
See <37ae047e16/lib/pleroma/application.ex (L83)>.

As explained in <https://ihatebeinga.live/objects/860d23e1-dc64-4b07-8b4d-020b9c56cff6>

> there are so many caches that clearing them all can nuke the supervisor, which by default will become an hero if it gets more than 3 restarts in <5 seconds

And further down the thread

> essentially we've got like 11 caches (37ae047e16/lib/pleroma/application.ex (L165))
> then in test we fetch them all (https://akkoma.dev/AkkomaGang/akkoma/src/branch/develop/test/support/data_case.ex#L50) and call clear on them
> so if this clear fails on any 3 of them, the pleroma supervisor itself will die

How it fails?

> idk maybe cachex dies, maybe :ets does a weird thing
> it doesn't log anything, it just consistently dies during cache clearing so i figured it had to be that

> honestly my best bet is locksmith and queuing
> https://github.com/whitfin/cachex/blob/master/lib/cachex/actions/clear.ex#L26
> clear is thrown into a locksmith transaction

> locksmith says
> >If the process is already in a transactional context, the provided function will be executed immediately. Otherwise the required keys will be locked until the provided function has finished executing.

> so if we get 2 clears too close together, maybe it locks, then doesn't like the next clear?

lib/pleroma/application.ex

@@ -112,7 +112,17 @@ defmodule Pleroma.Application do
 
     # See http://elixir-lang.org/docs/stable/elixir/Supervisor.html
     # for other strategies and supported options
-    opts = [strategy: :one_for_one, name: Pleroma.Supervisor]
+    # If we have a lot of caches, default max_restarts can cause test
+    # resets to fail.
+    # Go for the default 3 unless we're in test
+    max_restarts =
+      if @mix_env == :test do
+        100
+      else
+        3
+      end
+
+    opts = [strategy: :one_for_one, name: Pleroma.Supervisor, max_restarts: max_restarts]
     result = Supervisor.start_link(children, opts)
 
     set_postgres_server_version()