rust: fix false comment about mpsc::Sender We need Sync to share the Sender reference across threads.

resourceutil: fix location of line comments These comments slipped out of position when the sources where formatted with black in 2372284d9457.

rebase: avoid clobbering wdir() with --dry-run or --confirm (issue6291) See 56d3e0b499df for the source of adding originalwd to the list of things that cause wdir to be updated. That change didn't come with tests, and attempts to recreate the scenario described have thus far failed. Differential Revision: https://phab.mercurial-scm.org/D8489