Switch class loading logic in blackBoxWithJava tests

BoxWithJava tests now by default are loaded with the classloader which has
test's classpath in itself, as in the former ClassPathInTheSameClassLoaderTest

compiler/testData/codegen/boxWithJava/visibility/package/kt2781.java

@@ -0,0 +1,9 @@
+import java.lang.String;
+
+class J {
+    String value;
+
+    J(String value) {
+        this.value = value;
+    }
+}

compiler/testData/codegen/boxWithJava/visibility/package/kt2781.kt

@@ -0,0 +1 @@
+fun box() = J("OK").value

compiler/testData/codegen/boxWithJava/visibility/package/packageClass.java

@@ -0,0 +1,9 @@
+package protectedPack;
+
+import java.lang.String;
+
+class packageClass {
+    public String test() {
+        return "OK";
+    }
+}

compiler/testData/codegen/boxWithJava/visibility/package/packageClass.kt

@@ -0,0 +1,5 @@
+package protectedPack
+
+fun box(): String {
+   return packageClass().test()!!
+}

compiler/testData/codegen/boxWithJava/visibility/package/packageFun.java

@@ -0,0 +1,9 @@
+package protectedPack;
+
+import java.lang.String;
+
+public class packageFun {
+    String test() {
+        return "OK";
+    }
+}

compiler/testData/codegen/boxWithJava/visibility/package/packageFun.kt

@@ -0,0 +1,5 @@
+package protectedPack
+
+fun box(): String {
+   return packageFun().test()!!
+}

compiler/testData/codegen/boxWithJava/visibility/package/packageProperty.java

@@ -0,0 +1,7 @@
+package protectedPack;
+
+import java.lang.String;
+
+public class packageProperty {
+    String test = "OK";
+}

compiler/testData/codegen/boxWithJava/visibility/package/packageProperty.kt

@@ -0,0 +1,5 @@
+package protectedPack
+
+fun box(): String {
+   return packageProperty().test!!
+}