[Flutter] Some runtime JAR files in the classpath have an incompatible version. Consider removing them from the classpath No issues found 이런이런 에러

release apk 빌드시 저런 비스무레한 에러 발생하면 아래처럼 변경해 보자

위치 : app/src/build.gradle

 

before
dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk7:$kotlin_version"
}

after
dependencies {
    implementation "org.jetbrains.kotlin:kotlin-stdlib-jdk8:$kotlin_version"
}