added styling to the assignment details page for instructor and nav bar breadcrumbs

[ashwaqaljanahi2021]

…options section for the buttons to be placed next to the assignment, I added the description of the assignment as well in the assignment section. I also fixed the nav bar for the breadcrumbs, to be more uniform

Proposed changes

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If it fixes a bug or resolves a feature request, be sure to link to that issue using #{issue_number}.

I have updated the styling for the assignment details page for instructor as well as fixing the breadcrumbs for the nav bar to look more uniform, this is for issue #143

Types of changes

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• Bugfix (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)
• Documentation Update (if none of the other choices apply)

Checklist

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• My changeset covers only what is described above (no extraneous changes)
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

Further comments

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