Parametrize "Schema" name for ios build

[santiq]

It will be really useful if we could change the default schema name for ios build

quasar/app-vite/lib/modes/capacitor/capacitor-builder.js

Line 90 in 76b6b55

const args = `xcodebuild -workspace App.xcworkspace -scheme App -configuration ${buildType} -derivedDataPath`

To something like this

const args = `xcodebuild -workspace App.xcworkspace -scheme ${iosSchema || 'App'} -configuration ${buildType} -derivedDataPath`