(minor) outdated explanation in Appendix 02 Table B-3 "::path"

[kklibo]

• I have searched open and closed issues and pull requests for duplicates, using these search terms:
  • appendix 02
  • B-3
  • ::path
  • etc...
• I have checked the latest main branch to see if this has already been fixed, in this file:
  • appendix-02-operators.md

URL to the section(s) of the book with this problem: https://doc.rust-lang.org/book/appendix-02-operators.html

Description of the problem:
Outdated explanation of ::path in Appendix B: Table B-3
As of the 2018 edition, starting a path with :: refers to the extern prelude, rather than the crate root.
(source: https://doc.rust-lang.org/reference/paths.html#path-qualifiers)

Suggested fix:
Change explanation to

Path relative to the extern prelude (i.e., an explicitly absolute path)