feat(build): update gradle version to 6.5.1

Author: woowahan-pjs

build.gradle

@@ -9,6 +9,11 @@ repositories {
 }
 
 dependencies {
-    testCompile('org.junit.jupiter:junit-jupiter:5.5.2')
-    testCompile('org.assertj:assertj-core:3.14.0')
-}
+    testImplementation('org.junit.jupiter:junit-jupiter:5.7.0')
+    testImplementation('org.assertj:assertj-core:3.18.1')
+    testImplementation('org.mockito:mockito-inline:3.6.0')
+}
+
+test {
+    useJUnitPlatform()
+}

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,5 @@
-#Sun Mar 03 16:00:16 KST 2019
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.5.1-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.3-all.zip