fhemweb_sortable.js: don't allow any custom values in selected list when using sortable-strict

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fhemweb_sortable.js: don't allow any custom values in selected list when using sortable-strict

fhemweb_sortable.js: don't allow any custom values in selected list when using sortable-strictView Changes

Source: fhemweb_sortable.js: don't allow any custom values in selected list when using sortable-strict