Fix "MySQL | Import schema" task fails

[railakhmadullin]

SUMMARY

Reference to the issue #1662

ISSUE TYPE

• Bugfix Pull Request

COMPONENT NAME

community.zabbix.zabbix_server - initialize-mysql.yml

ADDITIONAL INFORMATION

[eb4x]

Can you add some more reasoning in the commit as to why we want to add use_shell: true, something about increased reliability? (I'm assuming that's what it's trying to achieve here)