Add parent dir to manifest classpath to account for paper-remapped load point.

Currently, the remapped WorldEdit jar on paper is loaded from a sub-directory of the plugins folder, meaning dependencies like truezip and rhino won't be found in the documented search locations. Adding the parent dir temporarily solves this.

See #2692.
Closes #2691.

Author: wizjany

buildSrc/src/main/kotlin/PlatformConfig.kt

@@ -151,7 +151,7 @@ fun Project.applyShadowConfiguration() {
 
 val CLASSPATH = listOf("truezip", "truevfs", "js")
     .map { "$it.jar" }
-    .flatMap { listOf(it, "FastAsyncWorldEdit/$it") }
+    .flatMap { listOf(it, "FastAsyncWorldEdit/$it", "../$it", "../FastAsyncWorldEdit/$it") }
     .joinToString(separator = " ")
 
 sealed class WorldEditKind(