spring boot 版本2.2.5 测试spring security 5.1.2时出现There is no PasswordEncoder mapped for the id "null" 因为spring security5.x版本更新了很多的密码加密模式，导致再进行输入密码时不设置密码加密模式无法匹配密码
There is no PasswordEncoder mapped for the id "null"
原文：https://www.cnblogs.com/YoungSone/p/12489254.html