Replace SystemClassLoader with the PlatformClassLoader

This ensures the bundler/deobfuscator can only see classes that are part
of the Java runtime, and not classes from the bundler/deobfuscator
themselves.

Signed-off-by: Graham <gpe@openrs2.dev>

bundler/src/main/java/dev/openrs2/bundler/Bundler.kt

@@ -44,7 +44,7 @@ class Bundler @Inject constructor(publicKeyTransformer: PublicKeyTransformer) {
         val glClient = Library.readPack(input.resolve("runescape_gl.pack200"))
 
         // bundle libraries together into a common classpath
-        val runtime = ClassLoader.getSystemClassLoader()
+        val runtime = ClassLoader.getPlatformClassLoader()
         val classPath = ClassPath(
             runtime,
             dependencies = listOf(unpacker),

deob/src/main/java/dev/openrs2/deob/Deobfuscator.kt

@@ -88,7 +88,7 @@ class Deobfuscator(private val input: Path, private val output: Path) {
         glUnpacker.remap(create(glUnpacker, "unpacker_"))
 
         // bundle libraries together into a common classpath
-        val runtime = ClassLoader.getSystemClassLoader()
+        val runtime = ClassLoader.getPlatformClassLoader()
         val classPath = ClassPath(
             runtime,
             dependencies = emptyList(),