Disable sequence output

Disabling sequence verbosity as those logs are of no use. Now git
doesn't depend on it and direclty uses trace function of logger so we
don't need to log sequence output on -vv

Change-Id: I1a34700f9d0309947ecbf29a3476a7b5287d5cea
diff --git a/x.go b/x.go
index f028bdc..2f22389 100644
--- a/x.go
+++ b/x.go
@@ -134,7 +134,7 @@
 	}
 	logger := log.NewLogger(loggerLevel, color)
 
-	ctx := tool.NewContextFromEnv(env, loggerLevel >= log.TraceLevel)
+	ctx := tool.NewContextFromEnv(env, false)
 	root, err := findJiriRoot(ctx.Timer())
 	if err != nil {
 		return nil, err