Avoid addShutdownHook to JVM during its shutdown

[thachlp]

Motivation:

Currently a JVM shutdown hook is added when DefaultClientFactory is used for the first time (code). It is possible that a JVM shutdown hook is being added after the JVM has started its shutdown and results in an exception below:

Caused by: java.lang.IllegalStateException: Shutdown in progress
    at java.base/java.lang.ApplicationShutdownHooks.add(ApplicationShutdownHooks.java:66)
    at java.base/java.lang.Runtime.addShutdownHook(Runtime.java:216)
    at grpc_shaded.com.linecorp.armeria.client.DefaultClientFactory.<clinit>(DefaultClientFactory.java:79)
    ... 24 more

Modifications:

• Skip adding the hook if we explicitly disabled it.
• Add try-catch for java.lang.IllegalStateException

Result:

• Closes Avoid addShutdownHook to JVM during its shutdown  #5494

[github-actions]

🔍 Build Scan® (commit: 9e3d696)

Job name	Status	Build Scan®
build-windows-latest-jdk-19	✅	https://ge.armeria.dev/s/ta52r3gubd2xy
build-self-hosted-unsafe-jdk-8	✅	https://ge.armeria.dev/s/2472na6j7wtpu
build-self-hosted-unsafe-jdk-19-snapshot-blockhound	✅	https://ge.armeria.dev/s/i3e4ft3qokwsq
build-self-hosted-unsafe-jdk-17-min-java-17-coverage	✅	https://ge.armeria.dev/s/dncalr6ntvoka
build-self-hosted-unsafe-jdk-17-min-java-11	✅	https://ge.armeria.dev/s/5mgdwt2zy75gu
build-self-hosted-unsafe-jdk-17-leak	✅	https://ge.armeria.dev/s/wb7an2udn6ali
build-self-hosted-unsafe-jdk-11	✅	https://ge.armeria.dev/s/6jb7ymzzwusgw
build-macos-12-jdk-19	✅	https://ge.armeria.dev/s/kwprfdkehgxe4

[ikhoon]

Thanks, @thachlp! 👍

[minwoox]

This doesn't do anything because the static initialization block is always called before static method(e.g. disableShutdownHook0() here).
Let's just catch the exception instead.

[thachlp]

Thanks for explain, updated 🙇

[jrhee17]

This doesn't do anything because the static initialization block is always called before static method(e.g. disableShutdownHook0() here).

Question) Would users still want to disable automatic shutdown to a later timing of their choosing by calling ClientFactory#disableShutdownHook? or is #1472 not an issue anymore?

[minwoox]

Looks good. Thanks!

[jrhee17]

Added some minor commits - let me know if any of the changes doesn't make sense. Thanks @thachlp ! 🙇 👍 🙇

[thachlp]

Added some minor commits - let me know if any of the changes doesn't make sense. Thanks @thachlp ! 🙇 👍 🙇

Thanks @jrhee17🙇