Enable Gradle configuration cache (#1646)

Enable the configuration cache feature in Gradle, and adjust various
pieces of build logic that aren't configuration cache compatible.

pkl-cli/pkl-cli.gradle.kts

@@ -13,7 +13,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-import java.io.ByteArrayOutputStream
 import java.io.OutputStream
 import org.gradle.kotlin.dsl.support.serviceOf
 
@@ -118,9 +117,15 @@ private fun setupJavaExecutableRun(
         null -> "java"
         else -> launcher.get().executablePath.asFile.absolutePath
       }
-    standardOutput = OutputStream.nullOutputStream()
 
-    args("-jar", tasks.javaExecutable.get().outputs.files.singleFile.toString(), *args)
+    doFirst { standardOutput = OutputStream.nullOutputStream() }
+
+    val javaExecutableFile = tasks.javaExecutable.map { it.outputs.files.singleFile }
+    argumentProviders.add(
+      CommandLineArgumentProvider {
+        listOf("-jar", javaExecutableFile.get().absolutePath) + args.toList()
+      }
+    )
 
     doFirst { outputFile.get().asFile.delete() }
 
@@ -133,7 +138,10 @@ val evalTestFlags = arrayOf("eval", "-x", "1 + 1", "pkl:base")
 
 fun Exec.useRootDirAndSuppressOutput() {
   workingDir = rootProject.layout.projectDirectory.asFile
-  standardOutput = ByteArrayOutputStream() // we only care that this exec doesn't fail
+  doFirst {
+    // we only care that this exec doesn't fail
+    standardOutput = OutputStream.nullOutputStream()
+  }
 }
 
 // 0.28 Preparing for JDK21 toolchains revealed that `testStartJavaExecutable` may pass, even though