Currently the ResolveConflicts RPC can take over 30 seconds to run. When
push rules are enabled, the `/api/v4/internal/allowed` currently takes
about 30 seconds for the gitlab-org/gitlab repository. In addition, with
Gitaly Cluster, since refs updates happen in a transaction, all nodes
also have to acknowledge the ref update for this RPC to finish
successfully. This can add even more time.

Until we solve https://gitlab.com/gitlab-org/gitlab/-/issues/335134,
let's bump the timeout from 30 to 60 seconds to allow for this RPC to do
all its work.

Changelog: changed