Fixes subscribeType metadata field not being respected for Pulsar pub sub

[elena-kolevska]

• Fixes subscribeType metadata field not being respected
• Fixes bug not allowing to connect to remote endpoints starting with pulsar:// or pulsar+ssl://

We have the subscribeType field documented, but the existing code implementation suggested we'd be reading that value off of the subscription metadata:

var defaultSubscription = &common.Subscription{
		PubsubName: pubsubName,
		Topic:      topicName,
		Route:      "/orders",
		Metadata:   map[string]string{"subscribeType": "key_shared"},
	}

Should we use what's set in the component file as default and override with the subscription metadata?

Issue reference

#3601

Checklist

Please make sure you've completed the relevant tasks for this PR, out of the following list:

• Code compiles correctly
• Created/updated tests
• Extended the documentation / Created issue in the https://github.com/dapr/docs/ repo: dapr/docs#[issue number]