A New Hampshire 18-year-old who completes boot camp this week is returning to his high school for his graduation, but was told he has to cover his new uniform if he wants to participate in the ceremony. Brandon Garabrant will graduate from Marine Corps Recruit Depot Parris Island on Friday, WMUR reported. He’ll then fly back to New Hampshire to attend his high school graduation and was planning to wear his new Marine Corps uniform there. But his mom told WMUR that the school’s principal emailed her to tell her that all students should wear school caps and gowns to…