Add Swift 6.0 to CI matrix

[kateinoigakukun]

No description provided.

[github-actions]

Time Change: +402ms (4%)

Total Time: 9,999ms

Test name	Duration	Change
Serialization/JavaScript function call through Wasm import	23ms	+3ms (11%)	⚠️
Serialization/JavaScript function call through Wasm import with int	17ms	+2ms (14%)	⚠️
Serialization/JavaScript function call from Swift	117ms	+9ms (7%)	🔍
Serialization/Swift Int to JavaScript with assignment	341ms	+26ms (7%)	🔍
Serialization/Swift String to JavaScript with assignment	399ms	+24ms (5%)	🔍

View Unchanged

Test name	Duration	Change
Serialization/Swift Int to JavaScript with call	1,054ms	+46ms (4%)
Serialization/JavaScript Number to Swift Int	311ms	+9ms (2%)
Serialization/Swift String to JavaScript with call	1,134ms	+52ms (4%)
Serialization/JavaScript String to Swift String	3,820ms	+175ms (4%)
Object heap/Increment and decrement RC	2,767ms	+56ms (2%)

View Baselines

Test name	Duration
Serialization/Call JavaScript function directly	3ms
Serialization/Assign JavaScript number directly	2ms
Serialization/Call with JavaScript number directly	3ms
Serialization/Write JavaScript string directly	5ms
Serialization/Call with JavaScript string directly	2ms