Update flask.md - Fix typos

Author: daniellozier

src/network-services-pentesting/pentesting-web/flask.md

@@ -10,11 +10,11 @@ Default cookie session name is **`session`**.
 
 ### Decoder
 
-Online Flask coockies decoder: [https://www.kirsle.net/wizards/flask-session.cgi](https://www.kirsle.net/wizards/flask-session.cgi)
+Online Flask cookies decoder: [https://www.kirsle.net/wizards/flask-session.cgi](https://www.kirsle.net/wizards/flask-session.cgi)
 
 #### Manual
 
-Get the first part of the cookie until the first point and Base64 decode it>
+Get the first part of the cookie until the first point and Base64 decode it:
 
 ```bash
 echo "ImhlbGxvIg" | base64 -d