Update plugin spotless to v7 (#454)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

gradle/libs.versions.toml

@@ -30,5 +30,5 @@ kotlinJvm = { id = "org.jetbrains.kotlin.jvm", version.ref = "kotlin" }
 dokka = { id = "org.jetbrains.dokka", version = "2.0.0" }
 mavenPublish = { id = "com.vanniktech.maven.publish", version = "0.30.0" }
 poko = { id = "dev.drewhamilton.poko", version = "0.18.2" }
-spotless = { id = "com.diffplug.spotless", version = "6.25.0" }
+spotless = { id = "com.diffplug.spotless", version = "7.0.1" }
 kotlinApiDump = { id = "org.jetbrains.kotlinx.binary-compatibility-validator", version = "0.17.0" }