tests: add bidirectional shutdown UDP tests

tests/test-dtls-resume.conf

@@ -1061,3 +1061,17 @@
 -a
 -v 2
 -l ADH-AES128-SHA
+
+# server DTLSv1.2 DHE-RSA-CHACHA20-POLY1305 bidirectional shutdown
+-u
+-r
+-v 3
+-l DHE-RSA-CHACHA20-POLY1305
+-w
+
+# client DTLSv1.2 DHE-RSA-CHACHA20-POLY1305 bidirectional shutdown
+-u
+-r
+-v 3
+-l DHE-RSA-CHACHA20-POLY1305
+-w

tests/test-dtls.conf

@@ -907,3 +907,11 @@
 -a
 -v 2
 -l ADH-AES128-SHA
+
+# server with bidirectional shutdown
+-l ECDHE-RSA-AES128-SHA256
+-w
+
+# client with bidirectional shutdown
+-l ECDHE-RSA-AES128-SHA256
+-w