[Web- html,css,javascript] Add save button to drawing app

[saikatdgp2001]

Description

Please include a summary of the change and which issue is fixed.

Fixes #49

Replace issue_no with the issue number which is fixed in this PR

Type of change

Please delete options that are not relevant.

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• [ ] My code follows the style guidelines(Clean Code) of this project
• [ ] I have performed a self-review of my own code
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have created a helpful and easy to understand README.md
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] I have added tests/screenshots(if any) that prove my fix is effective or that my feature works

[DevilsAutumn]

Everytime you start working on an issue make sure you fetch the remote repo to your local machine to prevent merge conflicts. Merge conflicts are quite confusing for beginner hence i would suggest you to read about merge conflicts and how to resolve them.

What you have to do now:

1. Run git fetch https://github.com/DevilsAutumn/Hacktoberfest22 main
2. Then you will see same conflicts in your local machine.
3. Accept the incoming changes and then do your changes again.
4. Then again add,commit and run git push -f

[saikatdgp2001]

done plz check

[DevilsAutumn]

Copy of #48