fix: graceful error message when server fails to start (#984)

* fix: graceful error message when server fails to start

Signed-off-by: wfnuser <wfnuser@126.com>

* fix: wordings

Signed-off-by: wfnuser <wfnuser@126.com>

internal/conf/path.go

@@ -122,7 +122,7 @@ func relativePath(subdir string) (dir string, err error) {
 		return confDir, nil
 	}
 
-	return "", fmt.Errorf("conf dir not found, please set KuiperBaseKey program environment variable correctly.")
+	return "", fmt.Errorf("dir %s not found, please make sure it is created.", confDir)
 }
 
 func ProcessPath(p string) (string, error) {