fix "label not found" error when options are indexed arrays

[SickRed]

with field options like

 InlineSelect::make('Title', 'attribute')->options([
                0 => 'Option 1',
                1 => 'Option 2',
                2 => 'Option 3'
            ])

the option label was not found due to strict type matching failing with numeric values. this PR fixes it by comparing the String version of values rather than the plain value