[ISSUE #12773] Fix unfriendly message when adding duplicate permissions.

[DirtyBit64]

What is the purpose of the change

Resolve the same issues in role management and permission management in the console : #12773.

Brief changelog

Modified com.alibaba.nacos.plugin.auth.impl.roles.NacosRoleServiceImpl.addXXX

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[github-actions]

Thanks for your this PR. 🙏
Please check again for your PR changes whether contains any usage/api/configuration change such as Add new API , Add new configuration, Change default value of configuration.
If so, please add or update documents(markdown type) in docs/next/ for repository nacos-group/nacos-group.github.io

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感谢您提交的PR。 🙏
请再次查看您的PR内容，确认是否包含任何使用方式/API/配置参数的变更，如：新增API、新增配置参数、修改默认配置等操作。
如果是，请确保在提交之前，在仓库nacos-group/nacos-group.github.io中的docs/next/目录下添加或更新文档（markdown格式）。

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 0% with 19 lines in your changes missing coverage. Please review.

Project coverage is 72.23%. Comparing base (2a0dafa) to head (446cb09).

Files with missing lines	Patch %	Lines
...s/plugin/auth/impl/roles/NacosRoleServiceImpl.java	0.00%	19 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             develop   #12891      +/-   ##
=============================================
- Coverage      72.25%   72.23%   -0.03%     
+ Complexity      9826     9825       -1     
=============================================
  Files           1287     1287              
  Lines          41445    41464      +19     
  Branches        4373     4383      +10     
=============================================
+ Hits           29947    29951       +4     
- Misses          9396     9410      +14     
- Partials        2102     2103       +1     

Files with missing lines	Coverage Δ
...s/plugin/auth/impl/roles/NacosRoleServiceImpl.java	24.20% <0.00%> (-3.34%)	⬇️

... and 2 files with indirect coverage changes

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