container: enter init path early

There is generally no use case where any setup is required before init, and requiring the explicit function call is error-prone and unnecessary. It also causes trouble with packages using a similar trick. This change moves argv0 check early and makes it an import side effect. The stub will be removed in v0.5.

Signed-off-by: Ophestra <cat@gensokyo.uk>

ldd/exec_test.go

@@ -2,12 +2,10 @@ package ldd_test
 
 import (
 	"errors"
-	"os"
 	"os/exec"
 	"testing"
 
 	"hakurei.app/check"
-	"hakurei.app/container"
 	"hakurei.app/ldd"
 	"hakurei.app/message"
 )
@@ -42,5 +40,3 @@ func TestExec(t *testing.T) {
 		}
 	})
 }
-
-func TestMain(m *testing.M) { container.TryArgv0(nil); os.Exit(m.Run()) }