Nil-check errors before printing them in VTOrc

[GuptaManan100]

Description

After moving away from external logging in #11085, we started seeing error messages like

E0901 16:38:28.412132   63266 topology_recovery_dao.go:112] <nil>
E0901 16:38:28.412186   63266 topology_recovery_dao.go:356] <nil>
E0901 16:38:28.412247   63266 topology_recovery_dao.go:260] <nil>
E0901 16:38:28.412352   63266 cluster_alias_dao.go:142] <nil>

The problem was traced to not doing a nil-check before printing the error message. The previous implementation of log.Errore used to do the nil-check before printing the error, so it wasn't required in the codebase.

Related Issue(s)

Checklist

• "Backport me!" label has been added if this change should be backported
• Tests were added or are not required
• Documentation was added or is not required

Deployment Notes

[vitess-bot]

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[rsajwani]

LGTM