RFR: 8332020: jwebserver tool prints invalid URL in case of IPv6 address binding [v3]

[Jaikiran Pai]

> Can I please get a review of this change which proposes to address https://bugs.openjdk.org/browse/JDK-8332020?
> 
> `jwebserver` when it is launched prints a URL where the server is accessible. When launched using an IPv6 bind address, the printed URL doesn't enclose the IPv6 literal in `[` `]` thus rendering it in the form:
> 
> URL http://0:0:0:0:0:0:0:1:8000/
> 
> This is an incorrect representation. As noted in RFC-2732 https://www.rfc-editor.org/rfc/rfc2732#section-2, the host literal is expected to be enclosed between `[` and `]`. 
> 
> The commit in this PR addresses that issues. A new jtreg test has been introduced to reproduce this issue and verify the fix.

Jaikiran Pai has updated the pull request incrementally with one additional commit since the last revision:

  Use -p 0 in the test
  
  Co-authored-by: Daniel Fuchs <67001856+dfuch at users.noreply.github.com>

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/19173/files
  - new: https://git.openjdk.org/jdk/pull/19173/files/4de8c13f..b8268744

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=19173&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=19173&range=01-02

  Stats: 1 line in 1 file changed: 0 ins; 0 del; 1 mod
  Patch: https://git.openjdk.org/jdk/pull/19173.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/19173/head:pull/19173

PR: https://git.openjdk.org/jdk/pull/19173