Migrated to latest gradle plugin. Upgraded kotlin and assertj version.

build.gradle

@@ -1,7 +1,7 @@
 plugins {
     id 'java'
-    id 'org.jetbrains.intellij' version '0.7.2'
-    id 'org.jetbrains.kotlin.jvm' version '1.5.20'
+    id 'org.jetbrains.intellij' version '1.1.3'
+    id 'org.jetbrains.kotlin.jvm' version '1.5.21'
     id 'jacoco'
     id 'com.github.kt3k.coveralls' version '2.11.0'
 }
@@ -22,10 +22,11 @@ repositories {
 
 dependencies {
     implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8"
-    testImplementation "org.assertj:assertj-core:3.19.0"
+    testImplementation "org.assertj:assertj-core:3.20.2"
     testImplementation 'org.junit.jupiter:junit-jupiter-api:5.8.0-M1'
     testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.8.0-M1'
     testImplementation "org.jetbrains.kotlin:kotlin-test"
+    testImplementation "org.jetbrains.kotlin:kotlin-reflect"
 //    testImplementation "org.jetbrains.kotlin:kotlin-test-junit"
 }
 
@@ -38,22 +39,22 @@ compileTestKotlin {
 }
 
 intellij {
-    version '2021.1.3' // LATEST-EAP-SNAPSHOT
-    updateSinceUntilBuild false
-    plugins = []
+    setVersion("2021.1.3") // LATEST-EAP-SNAPSHOT
+    setUpdateSinceUntilBuild(false)
+//    setPlugins(["com.intellij.java"])
 }
 
 patchPluginXml {
-    changeNotes """
+    setChangeNotes("""
   <h4>V0.1 (xx-Jun-21)</h4>
     <ul>
       <li>Initial.
     </ul>
   <p>Full changelog available at <a href="https://github.com/chrisly42/mc68000-asm-plugin#changelog">Github project site</a>.</p>
-"""
+""")
 }
 
-sourceSets.main.java.srcDirs 'src/main/gen'
+sourceSets.main.java.srcDirs('src/main/gen', 'src/main/java')
 
 test {
     useJUnitPlatform()
@@ -68,11 +69,11 @@ jacoco {
 
 jacocoTestReport {
     reports {
-        xml.required = true
-        csv.required = false
+        xml.required.set(true)
+        csv.required.set(false)
     }
 }
 
 publishPlugin {
-    token intellijPublishToken
+    setToken(intellijPublishToken)
 }