Fix tolerations help text in ChaosDelegate connection

[alebcay]

The current help text for --tolerations is duplicated from the --kubeconfig option right before it. This PR sets appropriate help text for the flag, with an example based on the definition of the Toleration struct:

litmusctl/pkg/types/agent_types.go

Lines 34 to 40 in eaf8030

	type Toleration struct {
	Key string `json:"key"`
	Value string `json:"value"`
	Operator string `json:"operator"`
	Effect string `json:"effect"`
	TolerationSeconds int `json:"tolerationSeconds"`
	}