The left-wing cofounder of a group that received gushing coverage for its efforts to “defund” conservative media will step away from the advocacy organization at the end of next month, The Post can reveal, following a legal challenge and attempts to rebrand in the wake of President Trump’s return to the White House. Nandini Jammi — whose Check My Ads Institute seeks to yank advertiser funding from right-wing figures and outlets purportedly spreading “disinformation” — announced on her LinkedIn “with enormous pride” that she was “stepping down.” The move comes on the heels of a funding shortfall amid impending legal...