add pgjwt tests (#1161)

Author: olirice

nix/tests/expected/pgjwt.out

@@ -0,0 +1,22 @@
+select
+  sign(
+    payload   := '{"sub":"1234567890","name":"John Doe","iat":1516239022}',
+    secret    := 'secret',
+    algorithm := 'HS256'
+  );
+                                                                            sign                                                                             
+-------------------------------------------------------------------------------------------------------------------------------------------------------------
+ eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiaWF0IjoxNTE2MjM5MDIyfQ.XbPfbIHMI6arZ3Y922BhjWgQzWXcXNrz0ogtVhfEd2o
+(1 row)
+
+select
+  verify(
+    token := 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJuYW1lIjoiRm9vIn0.Q8hKjuadCEhnCPuqIj9bfLhTh_9QSxshTRsA5Aq4IuM',
+    secret    := 'secret',
+    algorithm := 'HS256'
+  );
+                             verify                             
+----------------------------------------------------------------
+ ("{""alg"":""HS256"",""typ"":""JWT""}","{""name"":""Foo""}",t)
+(1 row)
+

nix/tests/sql/pgjwt.sql

@@ -0,0 +1,13 @@
+select
+  sign(
+    payload   := '{"sub":"1234567890","name":"John Doe","iat":1516239022}',
+    secret    := 'secret',
+    algorithm := 'HS256'
+  );
+
+select
+  verify(
+    token := 'eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJuYW1lIjoiRm9vIn0.Q8hKjuadCEhnCPuqIj9bfLhTh_9QSxshTRsA5Aq4IuM',
+    secret    := 'secret',
+    algorithm := 'HS256'
+  );