Copying a link to new visualization from dataset preview lacks current data source

[bprusinowski]

Currently, when copying a link to a new visualization from a given dataset preview, we do not include the data source, which can lead to potential errors if the person receiving the link has a different data source than the person sharing the link.

Link copied from Start a new visualization button (TEST): https://test.visualize.admin.ch/en/create/new?cube=https://energy.ld.admin.ch/sfoe/bfe_ogd84_einmalverguetung_fuer_photovoltaikanlagen/9

Corrected link: https://test.visualize.admin.ch/en/create/new?cube=https://energy.ld.admin.ch/sfoe/bfe_ogd84_einmalverguetung_fuer_photovoltaikanlagen/9&dataSource=Prod

[sosiology]

Tested with the example in the PR and LGTM. Thanks @bprusinowski