Remove a redundant null check in integration tests

Author: Abduqodiri Qurbonzoda

integration/src/main/kotlin/kotlinx/benchmark/integration/BenchmarkConfiguration.kt

@@ -8,10 +8,10 @@ class BenchmarkConfiguration {
     var mode: String? = null
     var outputTimeUnit: String? = null
     var reportFormat: String? = null
-    var includes: MutableList<String> = mutableListOf()
-    var excludes: MutableList<String> = mutableListOf()
-    var params: MutableMap<String, MutableList<Any>> = mutableMapOf()
-    var advanced: MutableMap<String, Any> = mutableMapOf()
+    private var includes: MutableList<String> = mutableListOf()
+    private var excludes: MutableList<String> = mutableListOf()
+    private var params: MutableMap<String, MutableList<Any>> = mutableMapOf()
+    private var advanced: MutableMap<String, Any> = mutableMapOf()
 
     fun include(pattern: String) {
         includes.add(pattern)
@@ -41,7 +41,7 @@ class BenchmarkConfiguration {
             reportFormat = ${reportFormat?.escape()}
             includes = ${includes.map { it.escape() }}
             excludes = ${excludes.map { it.escape() }}
-            ${params.entries.joinToString(separator = "\n") { """param("${it.key}", ${it?.value?.joinToString()})""" }}
+            ${params.entries.joinToString(separator = "\n") { """param("${it.key}", ${it.value.joinToString()})""" }}
             ${advanced.entries.joinToString(separator = "\n") {
                 """advanced("${it.key}", ${if (it.value is String) "\"${it.value}\"" else it.value})"""
             }}