AC-2 fixed issues found during Testing

[Divyanshusir]

Issue that this pull request solves

1. Students whose final registration is not verified ,their name will not be shown in final roll list
2. In place of batch year , working year used for preparing roll list
3. In place of 'semesterMarks' , 'Student_grades' model used for looking of student Grades for finding backlog courses
4. Decline button issue fixed during final verification

Closes: # (issue number)

Proposed changes

Brief description of what is fixed or changed

Types of changes

Put an x in the boxes that apply

• [x] 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)
• [ ] Other (please describe):

Checklist

Put an x in the boxes that apply

• [ ] My code follows the style guidelines of this project
• [ ] I have performed a self-review of my own code
• [ ] I have created new branch for this pull request
• [ ] I have commented my code, particularly in hard-to-understand areas
• [ ] I have made corresponding changes to the documentation
• [ ] My changes generate no new warnings
• [ ] My changes does not break the current system and it passes all the current test cases.

Screenshots

Please attach the screenshots of the changes made in case of change in user interface

Other information

Any other information that is important to this pull request

[Divyanshusir]

@ChaudharyRaman @prabhatsuman please merge this pr

[prabhatsuman]

LGTM