Build: Use same com.eclipsesource.j2v8 artifact for compilation

We can't reuse caches from different platform when we compile against
different jar on each platform. Since they have same api we may use
platform specific jars only for runtime.

js/js.engines/build.gradle.kts

@@ -1,4 +1,3 @@
-import org.gradle.internal.os.OperatingSystem
 
 plugins {
     kotlin("jvm")
@@ -10,18 +9,7 @@ dependencies {
     compile(project(":js:js.ast"))
     compile(project(":js:js.translator"))
     compileOnly(intellijCoreDep()) { includeJars("intellij-core") }
-
-    val currentOs = OperatingSystem.current()
-
-    when {
-        currentOs.isWindows -> {
-            val suffix = if (currentOs.toString().endsWith("64")) "_64" else ""
-            compileOnly("com.eclipsesource.j2v8:j2v8_win32_x86$suffix:4.6.0")
-        }
-        currentOs.isMacOsX -> compileOnly("com.eclipsesource.j2v8:j2v8_macosx_x86_64:4.6.0")
-        currentOs.run { isLinux || isUnix } -> compileOnly("com.eclipsesource.j2v8:j2v8_linux_x86_64:4.8.0")
-        else -> logger.error("unsupported platform $currentOs - can not compile com.eclipsesource.j2v8 dependency")
-    }
+    compileOnly("com.eclipsesource.j2v8:j2v8_linux_x86_64:4.6.0")
 }
 
 sourceSets {

js/js.tests/build.gradle.kts

@@ -76,7 +76,8 @@ dependencies {
         }
     }
 
-    testCompile(j2v8idString)
+    testCompileOnly("com.eclipsesource.j2v8:j2v8_linux_x86_64:4.8.0")
+    testRuntimeOnly(j2v8idString)
 
     testRuntime(kotlinStdlib())
     testJsRuntime(kotlinStdlib("js"))