Fix puppet-lint space_before_arrow violation in mysqlbackup.pp

[bronachfalls]

The require parameter in the mysql_user resource block in manifests/backup/mysqlbackup.pp had multiple spaces before => to align it with the other parameters above it:

require       => Class['mysql::server::root_password'],

While visually consistent with the aligned parameters above it, puppet-lint's space_before_arrow check enforces exactly one space before => in all cases. This was causing the spec/lint CI step to fail with:

WARNING: there should be a single space before '=>' on line 48,
column 11 (check: space_before_arrow)
Error: Process completed with exit code 1.

This is a pre-existing issue in the codebase unrelated to any recent changes — it would cause the lint step to fail on any PR's CI run.

Fix: remove the extra spaces so require follows the same single-space convention as all other => arrows in the file.

Summary

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Additional Context

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Related Issues (if any)

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Checklist

• 🟢 Spec tests.
• 🟢 Acceptance tests.
• Manually verified. (For example puppet apply)