terraform/jenkins: don't listen on port 80

This should use tls-alpn-01 on port 443 just fine.

terraform/jenkins/binary_cache.tf

@@ -99,7 +99,7 @@ resource "azurerm_network_security_group" "binary_cache_vm" {
     access                     = "Allow"
     protocol                   = "Tcp"
     source_port_range          = "*"
-    destination_port_ranges    = [22, 80, 443]
+    destination_port_ranges    = [22, 443]
     source_address_prefix      = "*"
     destination_address_prefix = "*"
   }