Remove unnecessary nil check in if statement in nodelease controller

[ZP-AlwaysWin]

What type of PR is this?
Remove unnecessary judgment
/kind cleanup

What this PR does / why we need it:

Which issue(s) this PR fixes:

Fixes #

OwnerReferences []OwnerReferencematches 
so nil len(OwnerReferences) ==0 

change:
 if lease.OwnerReferences == nil || len(lease.OwnerReferences) == 0 ==>if len(lease.OwnerReferences) == 0 

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

[k8s-ci-robot]

@ZP-AlwaysWin: Adding the "do-not-merge/release-note-label-needed" label because no release-note block was detected, please follow our release note process to remove it.

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[ZP-AlwaysWin]

/assgin @feiskyer

[mattjmcnaughton]

/lgtm
/release-note-none

Small nit: I think "Remove unnecessary nil check in if statement in nodelease controller` could be a slightly more descriptive pr title.

[ZP-AlwaysWin]

/lgtm
/release-note-none

Small nit: I think "Remove unnecessary nil check in if statement in nodelease controller` could be a slightly more descriptive pr title.

Thanks，I hava changed pr title.

[ZP-AlwaysWin]

/assign @Random-Liu