Fix docker building (#13681)

### What problem does this PR solve?

1. Refactor go server log
2. Update docker building, since nginx config should be set according to
the deployment.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)

---------

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

internal/server/local/admin_status.go

@@ -17,6 +17,8 @@
 package local
 
 import (
+	"fmt"
+	"ragflow/internal/logger"
 	"sync"
 )
 
@@ -66,6 +68,10 @@ func SetAdminStatus(status int, reason string) {
 	}
 	adminStatus.Status = status
 	adminStatus.Reason = reason
+
+	if adminStatus.Status != 0 {
+		logger.Warn(fmt.Sprintf("Admin server is unavailable, reason: %s", adminStatus.Reason))
+	}
 }
 
 // IsAdminAvailable returns true if admin is valid (Status == 0)