net.minecraftforge.gradle: Plugin not found

[CmdrNorthpaw]

I'm pretty sure that this is me being dumb, but after editing build.gradle to add Kottle, building Gradle throws a net.minecraftforge.gradle: Plugin not found error. Now after some Googling that error apparently occurs when you edit the part of build.gradle that should not be edited but that I did edit because of the whole avoiding compilation errors on Linux thing. Here's the offending part of the file:

buildscript {
    ext.kotlin_version = '1.3.70'
    repositories {
        maven { url = 'https://files.minecraftforge.net/maven' }
        jcenter()
        mavenCentral()
    }
    dependencies {
        classpath(group: 'net.minecraftforge.gradle', name: 'ForgeGradle', version: '3.+', changing: true) {
            exclude group: 'trove', module: 'trove'
    }
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
apply plugin: 'net.minecraftforge.gradle'

[CmdrNorthpaw]

Closed; dumb me misplaced a curly bracket.