rhg: upgrade dependencies
This upgrades all dependencies to their latest version, except `clap`, which
is upgraded to the last 2.x series version, since 3.x does not support our
minimum supported Rust version of 1.48.0.
This contains a security fix for `regex` which does not affect us too much, but
doesn't hurt, and the rest of the upgrades are there simply to keep up.
Differential Revision: https://phab.mercurial-scm.org/D12357
BasedOnStyle: LLVM
IndentWidth: 8
UseTab: ForIndentation
BreakBeforeBraces: Linux
AllowShortIfStatementsOnASingleLine: false
IndentCaseLabels: false
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AllowShortFunctionsOnASingleLine: false
IncludeCategories:
- Regex: '^<'
Priority: 1
- Regex: '^"'
Priority: 2