Test for incrementNonce() with data sourced from real run.

src/main/java/org/keepassxc/Connection.java

@@ -680,7 +680,7 @@ private byte[] ramdomGenerateNonce() {
      * @param nonce The nonce to be incremented.
      * @return nonce "+1".
      */
-    private byte[] incrementNonce(byte[] nonce) {
+    static byte[] incrementNonce(byte[] nonce) {
         var c = 1;
         byte[] incrementedNonce = nonce.clone();
 

src/test/java/org/keepassxc/ConnectionNonceTest.java

@@ -0,0 +1,19 @@
+package org.keepassxc;
+
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+
+class ConnectionNonceTest {
+    @Test
+    void test() {
+        byte[] before = new byte[] {
+            -1, 89, 10, 82, -100, 105, -57, 47, 124, -69, -39, -20, 80, -2, 17, 81, -26, 38, -14, -68, -44, -58, 98, -91
+        };
+        byte[] expected = new byte[] {
+            0, 90, 10, 82, -100, 105, -57, 47, 124, -69, -39, -20, 80, -2, 17, 81, -26, 38, -14, -68, -44, -58, 98, -91
+        };
+        byte[] actual = Connection.incrementNonce(before);
+        assertArrayEquals(expected, actual);
+    }
+}