Fix type/reason for drop

[vakalapa]

Fix the type for Drop. Ref: https://github.com/microsoft/retina/blob/078d15b3612dc2abacd77b01dc9e6413dd3dbb2a/pkg/utils/flow_utils.go#L106

Also, fix the dropreason number - https://github.com/cilium/cilium/blob/d13b89dc5d91b674272ded11104372e16fe937aa/api/v1/flow/flow.pb.go#L430

[github-actions[bot]]

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