Merge pull request #1928 from baomidou/dependabot/gradle/springBootVersion-2.2.2.RELEASE

Bump springBootVersion from 2.2.1.RELEASE to 2.2.2.RELEASE

build.gradle

@@ -24,7 +24,7 @@ ext {
         mybatisSpringVersion = '2.0.3',
         mybatisSpringBootStarterVersion = '2.1.1',
         springVersion = '5.2.2.RELEASE',
-        springBootVersion = '2.2.1.RELEASE',
+        springBootVersion = '2.2.2.RELEASE',
         jsqlparserVersion = '3.1',
         junitVersion = '5.5.2',
     ]