Don't require webServicePort to allow for TLS only listeners

[addisonj]

Describe the bug
In the code, webServicePort is marked as optional and in many places in the code, we properly check if it is present before starting a non TLS listener.

However, other paths in code are not properly checking this. For example:

pulsar/pulsar-broker/src/main/java/org/apache/pulsar/broker/namespace/NamespaceService.java

Lines 615 to 618 in bf00673

	if (LOG.isDebugEnabled()) {
	LOG.debug("Broker not found for SLA Monitoring Namespace {}",
	candidateBroker + ":" + config.getWebServicePort().get());
	}

This not the only instance, there are a number of other places, such as when functions is enabled.

To Reproduce
Steps to reproduce the behavior:

1. Run a broker with only TLS (set webServicePort= to empty)

Perform some actions and potentially get a crash

Expected behavior
We should not required webServicePort to be required and we should be properly checking everything for the optional usage.

[codelipenghui]

The issue had no activity for 30 days, mark with Stale label.

[JooHyukKim]

@tisonkun I check the git revision history and this issue seems to have been resolved by 18b2a20.

[tisonkun]

@JooHyukKim The commit is three year before this issue.

But the issued file now always check isPresent before get. So I agree we can close it as stale and feel free to open a new issue if similar symptom occurs in other place.

[tisonkun]

Thanks for bring up and invesitigation.

[JooHyukKim]

the issued file now always check isPresent before get

I may have provided wrong link, but you caught my intention right on "how" this issue was resolved 😄 @tisonkun Thank you