This commit adds some regression tests for using `jsxImportSource` in
the config file in combination with an import map.
These underlying issues were fixed by #15561.
Closes #13389
Closes #14723
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Co-authored-by: Aapo Alasuutari <aapo.alasuutari@gmail.com>
Co-authored-by: Bartek Iwańczuk <biwanczuk@gmail.com>
