docs: Add RFC for "Defining placement rules in SQL" (#18199)
docs: Add RFC for "Defining placement rules in SQL" (#18199)

 
coocood/tidb,EvilMcJerkface/tidb,pingcap/tidb,ngaut/tidb,kyle-wang/tidb,ngaut/tidb,ngaut/tidb,c4pt0r/tidb,c4pt0r/tidb,ngaut/tidb,pingcap/tidb,XuHuaiyu/tidb,XuHuaiyu/tidb,kyle-wang/tidb,kyle-wang/tidb,ngaut/tidb,ngaut/tidb,c4pt0r/tidb,pingcap/tidb,c4pt0r/tidb,pingcap/tidb,pingcap/tidb,kyle-wang/tidb,pingcap/tidb,coocood/tidb,kyle-wang/tidb,kyle-wang/tidb,c4pt0r/tidb,c4pt0r/tidb,EvilMcJerkface/tidb