Viewing own Directory Profile shows multiple markers

[andrewlimaza]

Describe the bug
When viewing your own profile from the Membership Directory, it shows all map markers and not just your own like if you were viewing another person's profile.

This is because the profile is missing the username from the path.

Broken: /membership-account/profile
Working: /membership-account/profile/myusername

To Reproduce
Steps to reproduce the behavior:

1. Go to xxx/membership-account/profile
2. See that multiple markers are shown.
3. Go to your own username profile from the Membership Directory, xxx/membership-account/profile/myusername
4. See that it's fixed.

See error when viewing your own profile without the username as part of the URL:

Expected behavior
Fix this issue when viewing your own profile if the username is missing. Fallback to the current user if logged-in. See around here - https://github.com/strangerstudios/pmpro-membership-maps/blob/dev/pmpro-membership-maps.php#L666

Isolating the problem (mark completed items with an [x]):

• I have deactivated other plugins and confirmed this bug occurs when only Paid Memberships Pro plugin is active.
• This bug happens with a default WordPress theme active, or Memberlite.
• I can reproduce this bug consistently using the steps above.