Use address reserved for docs in comment

[taksyon]

Addresses starting with "192.0.2.", "198.51.100.", or "203.0.113." are reserved for use in documentation and sample configurations. The original was some random french IP, just changed it to an address reserved for documentation by the Internet Assigned Numbers Authority

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[hkBst]

https://doc.rust-lang.org/nightly/std/net/struct.Ipv4Addr.html#method.is_global documents such addresses as not being global, so I expect the doc test to fail.

[rust-log-analyzer]

The job pr-check-2 failed! Check out the build log: (web) (plain enhanced) (plain)

Click to see the possible cause of the failure (guessed by this bot)

   0: __rustc::rust_begin_unwind
   1: core::panicking::panic_fmt
   2: core::panicking::assert_failed_inner
   3: core::panicking::assert_failed
   4: rust_out::main::_doctest_main_library_core_src_net_ip_addr_rs_291_0
   5: rust_out::main
   6: core::ops::function::FnOnce::call_once
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

---- library/core/src/net/ip_addr.rs - net::ip_addr::IpAddr::is_global (line 291) stdout end ----

[hkBst]

According to https://www.iana.org/assignments/iana-ipv4-special-registry/iana-ipv4-special-registry.xhtml, these special addresses are global:

192.175.48.0/24 	Direct Delegation AS112 Service 	[[RFC7534](https://www.iana.org/go/rfc7534)] 	1996-01 	N/A 	True 	True 	True 	True 	False
192.52.193.0/24 	AMT 	[[RFC7450](https://www.iana.org/go/rfc7450)] 	2014-12 	N/A 	True 	True 	True 	True 	False
192.31.196.0/24 	AS112-v4 	[[RFC7535](https://www.iana.org/go/rfc7535)] 	2014-12 	N/A 	True 	True 	True 	True 	False
192.0.0.10/32 	Traversal Using Relays around NAT Anycast 	[[RFC8155](https://www.iana.org/go/rfc8155)] 	2017-02 	N/A 	True 	True 	True 	True 	False
192.0.0.9/32 	Port Control Protocol Anycast 	[[RFC7723](https://www.iana.org/go/rfc7723)] 	2015-10 	N/A 	True 	True 	True 	True 	False

[taksyon]

seems like this is an awkward method to write good docs for in that case...

[tgross35]

IPs have a one-hot classification, being a documentation IP means it isn't global https://play.rust-lang.org/?version=nightly&mode=debug&edition=2024&gist=4d02d0c8fe5827b36b87a3b9dbbc0605. Based on the comment from @hkBst this also seems like a correct classification for the two IPs in question here.

seems like this is an awkward method to write good docs for in that case...

What makes the docs incorrect or bad?

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