Disable replica migration to avoid a race condition where the
migrated-from node turns into a replica.
Long term, this test should probably be improved to handle multiple
slots and accept such auto migrations but this is a quick fix to
stabilize the CI without completely dropping this test.
This is work in progress, focusing on two main areas:
* Avoiding race conditions with cluster configuration propagation.
* Ignoring limitations with redis-cli --cluster fix which makes it hard
to distinguish real errors (e.g. failure to fix) from expected
conditions in this test (e.g. nodes not agreeing on configuration).
Add tests for fixing migrating slot at all stages:
1. when migration is half inited on "migrating" node
2. when migration is half inited on "importing" node
3. migration inited, but not finished
4. migration is half finished on "migrating" node
5. migration is half finished on "importing" node
Also add tests for many simultaneous slot migrations.
Co-authored-by: Yossi Gottlieb <yossigo@gmail.com>
