Update tests/api/test_ossl_bn.c

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

Author: julek-wolfssl

tests/api/test_ossl_bn.c

@@ -346,7 +346,7 @@ int test_wolfSSL_BN_enc_dec(void)
         /* Exact size (no padding needed) */
         ExpectIntEQ(BN_bn2binpad(a, padOut, 1), 1);
         ExpectIntEQ(padOut[0], 0x02);
-        /* Zero-length for zero value */
+        /* Zero value padded to 3 bytes */
         ExpectIntEQ(BN_set_word(a, 0), 1);
         ExpectIntEQ(BN_bn2binpad(a, padOut, 3), 3);
         ExpectIntEQ(padOut[0], 0x00);