Ensure fact mysql_version exist when granting privileges to xtrabacku…

[ndelic0]

…p user in MySQL 8.0

Summary

PR should allow setting up xtrabackup configuration without breaking initial puppet run as mysql_version fact is not available in the catalog.

Additional Context

Add any additional context about the problem here.

• [ ] Root cause and the steps to reproduce. (If applicable)
• [ ] Thought process behind the implementation.

Related Issues (if any)

PR should fixed the issue reported https://github.com/puppetlabs/puppetlabs-mysql/issues/1576

Checklist

• [ ] 🟢 Spec tests.
• [ ] 🟢 Acceptance tests.
• [ ] Manually verified. (For example puppet apply) Reproduced issue [root@localhost production]# puppet apply -e 'include profile::mariadb'

  Warning: Module 'profile': Value returned from data_hash function 'yaml_data', when using location '/etc/puppetlabs/code/environments/production/modules/profile/data/common.yaml', must use keys qualified with the name of the module
  Error: Evaluation Error: Error while evaluating a Function Call, 'versioncmp' parameter 'a' expects a String value, got Undef (file: /etc/puppetlabs/code/environments/production/modules/mysql/manifests/backup/xtrabackup.pp, line: 53, column: 8) on node localhost.localdomain

  with fix applied

Notice: Compiled catalog for localhost.localdomain in environment production in 0.31 seconds
Notice: /Stage[main]/Profile::Mariadb/Package[mysql]/ensure: created
Notice: /Stage[main]/Profile::Mariadb/Package[mariadb]/ensure: created
Notice: /Stage[main]/Mysql::Server::Config/File[/etc/my.cnf.d]/ensure: created
Notice: /Stage[main]/Mysql::Server::Config/File[mysql-config-file]/ensure: defined content as '{sha256}e44307efdb246c98f0320b6f34b3cfc3931b25e3b6fa2f337b6b3ace65825567'
Notice: /Stage[main]/Mysql::Server::Install/Package[mysql-server]/ensure: created

in next puppet run backup configs will be applied.

[ndelic0]

@bastelfreak @alexjfisher I look forward to your feedback on the PR.