vinyl-luatest/select_consistency_test.lua is flaky. There are two distinct failures:

1. Divergent index:len().

   not ok 2	vinyl.select_consistency.defer_deletes:true.test_select_consistency
   #   ...tarantool/test/vinyl-luatest/select_consistency_test.lua:237: expected: 132077, actual: 132088
   #   stack traceback:
   #   	...tarantool/test/vinyl-luatest/select_consistency_test.lua:217: in function 
   'vinyl.select_consistency.defer_deletes:true.test_select_consistency'
   

   This is actually a bug caused by Invalid memory row count for multikey index with deferred deletes #10751.

2. Low dump count.

   not ok 1	vinyl.select_consistency.defer_deletes:false.test_select_consistency
   #   ...tarantool/test/vinyl-luatest/select_consistency_test.lua:200: Assertion failed: 9 >= 10
   #   stack traceback:
   #   	...tarantool/test/vinyl-luatest/select_consistency_test.lua:66: in function 'run_test'
   #   	...tarantool/test/vinyl-luatest/select_consistency_test.lua:212: in function 
   'vinyl.select_consistency.defer_deletes:false.test_select_consistency'
   

   This one looks false-positive: the test didn't ran long enough for 10 dumps to complete. We should either reduce the expected dump count or increase the test time.