Update pull.rebase option to merges.
Update pull.rebase option to merges.

* Fixes deprecation warning added in Git 2.22.
* "git rebase --preserve-merges is deprecated. Use --rebase-merges instead."
* https://megakemp.com/2019/03/20/the-case-for-pull-rebase/
* https://git-scm.com/docs/git-pull#Documentation/git-pull.txt---rebasefalsetruemergespreserveinteractive

joshukraine/dotfiles,joshukraine/dotfiles,joshukraine/dotfiles