feat: experiments logging improvements (#2049)

* feat: warn when enabling inactive experiments

* feat: TASK_ environment prefix

* feat: calculate experiment enabled/active instead of storing

* refactor: rename GetTaskVar to GetTaskEnv

* feat: experiments tests

cmd/task/task.go

@@ -69,7 +69,7 @@ func run() error {
 	}
 
 	if flags.Experiments {
-		return experiments.List(log)
+		return log.PrintExperiments()
 	}
 
 	if flags.Init {
@@ -109,6 +109,10 @@ func run() error {
 		dir = home
 	}
 
+	if err := experiments.Validate(); err != nil {
+		log.Warnf("%s\n", err.Error())
+	}
+
 	var taskSorter sort.TaskSorter
 	switch flags.TaskSort {
 	case "none":
@@ -154,9 +158,6 @@ func run() error {
 	if err != nil {
 		return err
 	}
-	if experiments.AnyVariables.Enabled {
-		log.Warnf("The 'Any Variables' experiment flag is no longer required to use non-map variable types. If you wish to use map variables, please use 'TASK_X_MAP_VARIABLES' instead. See https://github.com/go-task/task/issues/1585\n")
-	}
 
 	// If the download flag is specified, we should stop execution as soon as
 	// taskfile is downloaded