去除slf4j-api

mybatis-plus-generate/build.gradle

@@ -1,7 +1,6 @@
 dependencies {
     compile project(":mybatis-plus-support")
     compileOnly rootProject.ext.dependencies["velocity"]
-    compile rootProject.ext.dependencies["slf4j-api"]
     testCompile rootProject.ext.dependencies["sqlserver"]
     testCompile rootProject.ext.dependencies["postgresql"]
     testCompile rootProject.ext.dependencies["oracle"]