build: pin JVM toolchains to Java 17

build.gradle

@@ -37,6 +37,8 @@ if ((project.hasProperty('SONATYPE_USER') || System.getenv('SONATYPE_USER') != n
 }
 
 allprojects {
+    apply from: rootProject.file("gradle/templates/defaultJavaSettings.gradle")
+
     repositories {
         mavenCentral()
         google()

gradle/templates/defaultJavaSettings.gradle

@@ -0,0 +1,11 @@
+plugins.withId('org.jetbrains.kotlin.multiplatform') {
+    kotlin {
+        jvmToolchain(17)
+    }
+}
+
+plugins.withId('org.jetbrains.kotlin.jvm') {
+    kotlin {
+        jvmToolchain(17)
+    }
+}