Though there's every chance it was discovered too late, Reddit user Snow-Spyder had the bright idea of turning shining a UV torch onto the contents on the Destiny 2 Limited Edition bundle. And it worked.
By 'worked', we mean it actually served a purpose. Upon hitting the included map with those UV rays, they discovered that it had been hiding some extra information all this time.
It's early days yet for the internet sleuths of Reddit, but for those completely ok with a couple of little spoilers, it seems 100% likely that the sigils and markings relate to the recently released Leviathan raid.
As a non-player until the PC version arrives, all I can link up here is how the sun, axes, and beast sigils match what's displayed on Emperor Calus' face during an early, repeating phase of his fight. I also notice heavy use of arrow markings in the map, which could relate to the Gauntlet puzzle everyone struggled to work out on launch day.
Reddit users are under the impression that the links between each sigil represent an 'order' in a some way, with the original poster mentioning that there are two hard to see diamond shapes under the sun marking, with one being misalaigned against the link linking 2 and 3. Make of that what you will.
The only person certain of what this could be is another Reddit user who, after running the info back to a friend, suggests it's just a map relating to the entrance of the raid itself. Was it hard to find? Are they just the various entrances used to access each area? We'll likely have solid answers once some more people gaze upon its mysteries.