upgrade fluidsynth and fix missing symbol in recent xmake

[jingkaimori]

• Before adding new features and new modules, please go to issues to submit the relevant feature description first.
• Write good commit messages and use the same coding conventions as the rest of the project.
• Please commit code to dev branch and we will merge into master branch in feature
• Ensure your edited codes with four spaces instead of TAB.

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• 增加新特性和新模块之前，请先到issues提交相关特性说明，经过讨论评估确认后，再进行相应的代码提交，避免做无用工作。
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更新fluidsynth到2.3.5，并修复链接错误。取代 #3854 。

[jingkaimori]

Why macos test fails with such message?

@programdir/core/main.lua:329: @programdir/modules/private/action/require/impl/package.lua:1115: package(libiconv/latest:{}): conflict dependencies with package(libiconv/latest/system:{}) in fluidsynth!

[jingkaimori]

本地用Ubuntu22.04LTS虚拟机，从apt安装cmake，运行测试脚本的时候不会报错，为什么ci就报错？

[Issues-translate-bot]

Bot detected the issue body's language is not English, translate it automatically.

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I use Ubuntu22.04LTS virtual machine locally and install cmake from apt. No error is reported when running the test script. Why does ci report an error?