[fix][cli] Fix V5 scalable-topics property parsing

[void-ptr974]

Fixes #26176

Motivation

The V5 scalable-topics CLI consumed the topic or namespace argument as a -p / --property value when -p was placed before the positional argument.

Examples:

pulsar-admin scalable-topics create -p app=cli topic://public/default/t1
pulsar-admin scalable-topics list -p app=cli public/default

Modifications

• Make -p / --property consume one value per occurrence.
• Keep repeated -p key=value support.
• Support comma-separated properties, such as -p key=value,key2=value2.
• Add CLI parser tests for create and list.

After this change, both forms are accepted:

pulsar-admin scalable-topics create -p app=cli -p mode=blackbox topic://public/default/t1
pulsar-admin scalable-topics create -p app=cli,mode=blackbox topic://public/default/t1

Verifying this change

• Make sure that the change passes the CI checks.

This change added tests and can be verified as follows:

• ./gradlew --no-daemon :pulsar-client-tools:test --tests org.apache.pulsar.admin.cli.TestCmdScalableTopics
• ./gradlew --no-daemon :pulsar-client-tools:checkstyleMain :pulsar-client-tools:checkstyleTest

Does this pull request potentially affect one of the following parts:

• Dependencies (add or upgrade a dependency)
• The public API
• The schema
• The default values of configurations
• The threading model
• The binary protocol
• The REST endpoints
• The admin CLI options
• The metrics
• Anything that affects deployment