fixes #269

[sarnava1]

Checklist

• [x] I have read the Contribution & Best practices Guide and my PR follows them.
• [x] There is a corresponding issue for this pull request.
• [x] My branch is up-to-date with the Upstream master branch.
• [ ] The unit tests pass locally with my changes (provide a screenshot or link for test)
• [ ] I have added tests that prove my fix is effective or that my feature works
• [ ] I have added necessary documentation (if appropriate)

Short description of what this resolves:

This PR solves the fundamental issue that different favicons were appearing in template.html and build.html which should not be. There should be a unique favicon across all pages and since we had the favicon in template.html which was defined for various screen sizes explicitly, I think that would solve our issue efficiently.

Fixes #269

[sarnava1]

@tabesin I think this was necessary.

[championpaddler]

@sarnava1 Both the icons are same.

[tabesin]

This is to be solved via https://github.com/fossasia/meilix-generator/issues/266