java: add «2683. Neighboring Bitwise XOR»

URL:	https://leetcode.com/problems/neighboring-bitwise-xor/
Signed-off-by: Matej Focko <me@mfocko.xyz>

java/neighboring-bitwise-xor.java

@@ -0,0 +1,11 @@
+class Solution {
+  public boolean doesValidArrayExist(int[] derived) {
+    var cumXor = 0;
+
+    for (var x : derived) {
+      cumXor ^= x;
+    }
+
+    return cumXor == 0;
+  }
+}