[improve][testing] Add client/admin builders and temporary directory support for testing standalone service

[hohoho1886]

Fixes #10473

Motivation

This PR aims to make testing with PulsarStandalone more convenient because:

• In PulsarStandaloneBuilder, there are no helper methods to create a PulsarClient or PulsarAdmin connected to the started service.
• When testing, messages are written to disk and test data persist there even when the service is stopped.

Modifications

• Add buildClient() and buildAdmin() methods
• Implement a method which creates temporary directories, then delete them in close() (which should be called at the end of the test) of PulsarStandalone
• Adapt startBookieWithMetadataStore() to start the service without .conf file. I think this is safe in production because else branch is never executed as long as .conf file is provided (which is the case in production)

Otherwise, I am ready to address any requested changes.

Verifying this change

• Make sure that the change passes the CI checks.

(Please pick either of the following options)

This change added tests and can be verified as follows:

• Added PulsarStandaloneBuilderTest.testStartFromJava, which starts a
  standalone service from plain Java with a client and check if temporary directory is deleted after the service is closed.
• Note: I set standalone.setNumOfBk(2) to avoid the error of not having enough healthy bookies.

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

If the box was checked, please highlight the changes

• 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