CocoaPod build fails

[mbvs]

Describe the problem adding Verovio as a CocoaPod dependency to an Xcode Project fails while building

To Reproduce

• add a podfile with following content:

  platform :ios, '14.0'
  use_frameworks!
  target 'NoteNinja' do
  pod 'Verovio', :git => 'https://github.com/rism-digital/verovio.git', :branch => 'develop'
  end

• run pod install
• open generated <app>.xcworkspace
• build project
• build fails with following warnings and errors:

  
  2 warnings generated.

/Users/marcus/Projects/NoteNinja/NoteNinja/Pods/Verovio/src/toolkit.cpp:387:31: 'codecvt_utf8' is deprecated

/Users/marcus/Projects/NoteNinja/NoteNinja/Pods/Verovio/src/toolkit.cpp:387:10: 'wstring_convert<std::codecvt_utf8, char16_t>' is deprecated

4 errors generated.

/Users/marcus/Projects/NoteNinja/NoteNinja/Pods/Verovio/src/resources.cpp:172:32: No member named 'contains' in 'std::unordered_map<char32_t, vrv::Glyph>'

/Users/marcus/Projects/NoteNinja/NoteNinja/Pods/Verovio/src/resources.cpp:177:31: No member named 'contains' in 'std::unordered_map<char32_t, vrv::Glyph>'

/Users/marcus/Projects/NoteNinja/NoteNinja/Pods/Verovio/src/resources.cpp:191:29: No member named 'contains' in 'std::unordered_map<std::string, char32_t>'

/Users/marcus/Projects/NoteNinja/NoteNinja/Pods/Verovio/src/resources.cpp:200:37: No member named 'contains' in 'std::unordered_map<char32_t, vrv::Glyph>'

I reckon this happens because std::unordered_map::contains requires C++20 and the podspec file defines `"CLANG_CXX_LANGUAGE_STANDARD" => "c++17"` Unfortunately setting the C++ Language Dialect in the Build Settings for the Pods Project doesn't work

**Environment information (as appropriate)**
 - MacBook M1 Pro, MacOS Sonoma 14.2.1, XCode 15.3
 - Verovio 4.1.0

[lpugin]

Any possible relation with #3472 ?

[mbvs]

Any possible relation with #3472 ?

nope - the code is pulled directly from git - as configured in the podfile.

In the meantime I made a fork and changing the podspec line to "CLANG_CXX_LANGUAGE_STANDARD" => "c++20" solved the problem as assumed.

[lpugin]

Fixed here https://github.com/rism-digital/verovio/commit/6a790ffacd81532a386675a70e5fd3debed6791e

[mbvs]

Thanks alot!