Remove deprecated field template.Name in favour of template.Ref

[khrm]

Changes

Fixes #911

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Release Notes

Deprecated field template.Name in has been removed in favor of template.Ref

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-triggers-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/apis/triggers/v1alpha1/trigger_validation.go	94.4%	94.0%	-0.3
pkg/template/resource.go	98.3%	100.0%	1.7

[tekton-robot]

The following is the coverage report on the affected files.
Say /test pull-tekton-triggers-go-coverage to re-run this coverage report

File	Old Coverage	New Coverage	Delta
pkg/apis/triggers/v1alpha1/trigger_validation.go	94.4%	94.0%	-0.3
pkg/template/resource.go	98.3%	100.0%	1.7

[tekton-robot]

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This pull-request has been approved by: savitaashture

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[dibyom]

/lgtm