pd: update placement rules (#4530)
pd: update placement rules (#4530)

* pd: update placement rules

Signed-off-by: disksing <042dc4512fa3d391c5170cf3aa61e6a638f84342@disksing.com>

* Update configure-placement-rules.md

Co-authored-by: TomShawn <3d0966147538bc5ab020e8dffa2c0b746f9728a6@users.noreply.github.com>

* Update configure-placement-rules.md

Co-authored-by: TomShawn <3d0966147538bc5ab020e8dffa2c0b746f9728a6@users.noreply.github.com>

* Update configure-placement-rules.md

Co-authored-by: TomShawn <3d0966147538bc5ab020e8dffa2c0b746f9728a6@users.noreply.github.com>

* Update configure-placement-rules.md

Co-authored-by: TomShawn <3d0966147538bc5ab020e8dffa2c0b746f9728a6@users.noreply.github.com>

* Update configure-placement-rules.md

Co-authored-by: TomShawn <3d0966147538bc5ab020e8dffa2c0b746f9728a6@users.noreply.github.com>

Co-authored-by: TomShawn <3d0966147538bc5ab020e8dffa2c0b746f9728a6@users.noreply.github.com>
pingcap/docs-cn,pingcap/docs-cn