The pro-Gov. Kathy Hochul message is going out to millions of New Yorkers, landing in their mailboxes right before the Democratic primary next week. No, this isn’t a fancy color campaign flyer paid for from her considerable war chest touting our endorsement, but a plain, 8.5-inch by 3.5-inch document from the state Tax Department. It begins with this merry greeting: “Gov. Hochul and the New York State Legislature are providing you this Homeowner Tax Rebate check that you can use to help pay your property taxes.” A check for a couple hundred bucks is enclosed. While tax rebates are fine — we wa…