fix various issues

- typo error
- replace `ssl->hanshake` with handshake

Signed-off-by: Jerry Yu <jerry.h.yu@arm.com>
diff --git a/tests/opt-testcases/tls13-kex-modes.sh b/tests/opt-testcases/tls13-kex-modes.sh
index 2681f61..974d513 100755
--- a/tests/opt-testcases/tls13-kex-modes.sh
+++ b/tests/opt-testcases/tls13-kex-modes.sh
@@ -18,7 +18,7 @@
 # limitations under the License.
 #
 
-# DO NOT ADD NEW TEST CASES INTO THIS FILE. The left cases can be generated by
+# DO NOT ADD NEW TEST CASES INTO THIS FILE. The left cases will be generated by
 # scripts in future(#6280)
 
 requires_gnutls_tls1_3