Resolve "Illustration > Update activity"

Purpose

Based on #364 (closed), https://gitlab.com/gitlab-org/gitlab/-/issues/358587, https://gitlab.com/gitlab-org/gitlab/-/issues/358564 update and rename activity illustration

Screenshots

before	after

Checklist

For a new icon and/or illustration:

• Link to related design issue: #364 (closed)
• If this adds an icon ensure that it follows the new icon checklists.
• If this adds an illustration ensure that it follows the new illustration checklists.

For third-party trademarks:

• If this adds or updates an icon or illustration that includes a third-party trademark, ensure that it follows the process for adding third-party trademarks to GitLab.

Closes #364 (closed)