[K/N] Treat nativeGCAfterIteration as a boolean parameter instead of a string

Author: Abduqodiri Qurbonzoda

examples/kotlin-multiplatform/build.gradle

@@ -80,7 +80,7 @@ benchmark {
             iterations = 5
             iterationTime = 300 // time in ms per iteration
             iterationTimeUnit = "ms" // time in ms per iteration
-            advanced("nativeGCAfterIteration", "true")
+            advanced("nativeGCAfterIteration", true)
         }
 
         csv {

runtime/commonMain/src/kotlinx/benchmark/BenchmarkReportFormatter.kt

@@ -175,7 +175,7 @@ private object JsonBenchmarkReportFormatter : BenchmarkReportFormatter() {
           ${result.params.entries.joinToString(separator = ",\n          ") { "\"${it.key}\" : \"${it.value}\"" }}
     },
     "nativeFork" : "${result.config.nativeFork.toText()}",
-    "nativeGCAfterIteration" : "${result.config.nativeGCAfterIteration}",
+    "nativeGCAfterIteration" : ${result.config.nativeGCAfterIteration},
     "primaryMetric" : {
        "score": ${result.score},
        "scoreError": ${result.error},