fix: panic when using --list and --silent

[pd93]

Fixes #1509

• fix: setup logger if nil when listing task names
• refactor: bubble errors from ListTaskNames

@andreynering An alternative approach to fixing this would be the following diff. It would simplify the code as we no longer have to conditionally load the taskfile/logger in ListTaskNames(). This obviously comes with a slight performance cost.

diff --git a/cmd/task/task.go b/cmd/task/task.go
index f3144703..17f9884c 100644
--- a/cmd/task/task.go
+++ b/cmd/task/task.go
@@ -264,15 +264,15 @@ func run() error {
                return err
        }
 
+       if err := e.Setup(); err != nil {
+               return err
+       }
+
        if (listOptions.ShouldListTasks()) && flags.silent {
                e.ListTaskNames(flags.listAll)
                return nil
        }
 
-       if err := e.Setup(); err != nil {
-               return err
-       }
-
        // If the download flag is specified, we should stop execution as soon as
        // taskfile is downloaded
        if flags.download {