Add profile pic and correct usage of banner link

create_db.sql

@@ -11,7 +11,7 @@ CREATE TABLE users (
     first_name          VARCHAR(255)    NOT NULL,
     last_name           VARCHAR(255)    NOT NULL,
     email               VARCHAR(255)    NOT NULL,
-    -- profile_pic_link    VARCHAR(255)    NOT NULL,
+    profile_pic_link    VARCHAR(255),
     role                INT             NOT NULL,
     PRIMARY KEY (id)
 );
@@ -26,7 +26,7 @@ CREATE TABLE articles (
     id              INT             AUTO_INCREMENT,
     title           VARCHAR(255)    NOT NULL,
     created         TIMESTAMP       DEFAULT CURRENT_TIMESTAMP,
-    banner_link     VARCHAR(255)    NOT NULL,
+    banner_link     VARCHAR(255),
     summary         TEXT            NOT NULL,
     published       BOOL            NOT NULL,
     rejected        BOOL            NOT NULL,