Chart showing issues created per month

What does this MR do?

This MR adds a chart showing issues created per month for groups.

Issues Chart	Empty State (No Data)	Empty State (Filters)

closes #7478 (closed)

What are the relevant issue numbers?

#7478 (closed)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests added for this feature/bug
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides
• EE specific content should be in the top level /ee folder
• For a paid feature, have we considered GitLab.com plans, how it works for groups, and is there a design for promoting it to users who aren't on the correct plan? Yes, this is handled in https://gitlab.com/gitlab-org/gitlab-ee/issues/8037.

app/assets/images/koding-logo.svg

-<?xml version="1.0" encoding="utf-8"?>
-<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 12 14">
-    <g fill="#d6d7d9">
-        <path d="M8.7 0L5.3.3l3.2 6.8-3.2 6.6 3.5.3L12 6.9z"/>
-        <ellipse cx="1.7" cy="11.1" rx="1.7" ry="1.7"/>
-        <ellipse cx="1.7" cy="5.6" rx="1.7" ry="1.7"/>
-    </g>
-</svg>
\ No newline at end of file