[UPDATE] Update Gradle, IntelliJ Plugin, IntelliJ version and code co…

…mpatibility level

build.gradle

@@ -1,30 +1,28 @@
 plugins {
     id 'java'
-    id 'org.jetbrains.intellij' version '0.4.2'
+    id 'org.jetbrains.intellij' version '0.7.2'
 }
 
 group 'com.liferay'
 version '1.0-SNAPSHOT'
 
-sourceCompatibility = 1.8
+sourceCompatibility = 11
+targetCompatibility = 11
 
 repositories {
     mavenCentral()
 }
 
 dependencies {
-    testCompile group: 'junit', name: 'junit', version: '4.12'
+    testImplementation group: 'junit', name: 'junit', version: '4.12'
 }
 
 intellij {
-    version '2018.3.4'
+    plugins 'gradle'
+    version '2020.3.3'
 }
 
 patchPluginXml {
-    changeNotes """
-      Add change notes here.<br>
-      <em>most HTML tags may be used</em>"""
-
-    sinceBuild "183"
+    sinceBuild "203"
     untilBuild ""
 }

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,5 @@
-#Thu Feb 14 00:00:23 CST 2019
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.8.3-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.10-all.zip