add delete player method to AccessClient and test

fh.fd.ci.client/src/main/java/de/fd/fh/network/AccessClient.java

@@ -20,4 +20,7 @@ public interface AccessClient
     @RequestLine("POST /accounts/logout")
     @Headers(Utils.AUTHENTICATION_HEADER + ":Bearer {authToken}")
     Response logout(@Param("authToken") final String authenticationHeader);
+
+    @RequestLine("DELETE /accounts/{playerId}")
+    Response deletePlayer(@Param("playerId") final String playerId);
 }

fh.fd.ci.client/src/test/java/de/fd/fh/network/AccessClientTest.java

@@ -83,4 +83,14 @@ class AccessClientTest
 
         assertEquals(200, result.status(), "Should return status code 200.");
     }
+
+    @Test
+    void testDeletePlayer()
+    {
+        mockClient.ok(HttpMethod.DELETE, "/accounts/12345");
+
+        final Response result = client.deletePlayer("12345");
+
+        assertEquals(200, result.status(), "Should return status code 200.");
+    }
 }