Changed dependencies of custom tests on build

Now running "gradle test --tests ..." works as expected.

Author: elizarov

core/kotlinx-coroutines-core/build.gradle

@@ -24,14 +24,16 @@ task lockFreedomTest(type: Test, dependsOn: testClasses) {
             sourceSets.test.output.classesDirs)
     include '**/*LFTest.*'
 }
-test.dependsOn lockFreedomTest
+
+build.dependsOn lockFreedomTest
 
 task jdk16Test(type: Test, dependsOn: testClasses) {
     executable = "$System.env.JDK_16/bin/java"
     exclude '**/*LinearizabilityTest.*'
     exclude '**/*LFTest.*'
 }
-test.dependsOn jdk16Test
+
+build.dependsOn jdk16Test
 
 task testsJar(type: Jar, dependsOn: testClasses) {
     classifier = 'tests'