Add problem_solution.html

[baranwalayush]

#156

Made the questions clickable to see the solutions of the selected question

• Updated the app.py file to show the code solution of selected question to the user
• Added problem_solution.html file which will be displayed when the code has to be shown.
• Rendered it using flask to connect with the solutions.

Now, the website is functional and any user can select a programming language and then select among various questions to check for its solution.

[d-coder111]

Looks good😊✌..keep contributing..keep learning🚀👍