test: flaky box/ddl_collation_deleted_gh-3290.test.lua test

[avtikhon]

Tarantool version:
Tarantool 2.7.0-24-g050c23b75
Target: Darwin-x86_64-RelWithDebInfo
Build options: cmake . -DCMAKE_INSTALL_PREFIX=/usr/local -DENABLE_BACKTRACE=ON
Compiler: /Library/Developer/CommandLineTools/usr/bin/cc /Library/Developer/CommandLineTools/usr/bin/c++
C_FLAGS: -Wno-unknown-pragmas -fexceptions -funwind-tables -fno-omit-frame-pointer -fno-stack-protector -fno-common -msse2 -std=c11 -Wall -Wextra -Wno-strict-aliasing -Wno-char-subscripts -Wno-gnu-alignof-expression -Werror
CXX_FLAGS: -Wno-unknown-pragmas -fexceptions -funwind-tables -fno-omit-frame-pointer -fno-stack-protector -fno-common -msse2 -std=c++11 -Wall -Wextra -Wno-strict-aliasing -Wno-char-subscripts -Wno-invalid-offsetof -Wno-gnu-alignof-expression -Werror

OS version:
OSX 13

Bug description:
https://gitlab.com/tarantool/tarantool/-/jobs/832103286#L4039

artifacts.zip

results file checksum: 4a0a0ea618b9baf9fdd9826e83191576

[002] --- box/ddl_collation_deleted_gh-3290.result	Wed Sep 30 17:19:31 2020
[002] +++ /tmp/tnt/rejects/box/ddl_collation_deleted_gh-3290.reject	Thu Nov  5 15:58:58 2020
[002] @@ -12,5 +12,5 @@
[002]   | ...
[002]  box.space._collation:replace(t)
[002]   | ---
[002] - | - [1, 'unicode', 1, 'ICU', '', {'strength': 'tertiary'}]
[002] + | - [1]
[002]   | ...
[002] 

Steps to reproduce:

Optional (but very desirable):

• coredump
• backtrace
• netstat