Reduce differences between CE and EE code base in reports components

What does this MR do?

Reduce differences between CE and EE code base in reports components.

This morning I resolved this conflicts in ce-to-ee MR: https://gitlab.com/gitlab-org/gitlab-ee/merge_requests/6863 By updating the paths in CE the conflicts will have fewer chances to happen again.

EE files:

• https://gitlab.com/gitlab-org/gitlab-ee/blob/master/app/assets/javascripts/reports/components/report_issues.vue
• https://gitlab.com/gitlab-org/gitlab-ce/blob/master/app/assets/javascripts/reports/components/issues_list.vue

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides