[Java][Spring] default value for list parameter

[borsch]

Fix for #11957

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[wing328]

cc @cachescrubber (2022/02) @welshm (2022/02) @MelleD (2022/02) @atextor (2022/02) @manedev79 (2022/02) @javisst (2022/02) @borsch (2022/02) @banlevente (2022/02)

[welshm]

This looks great - I think I would just add a test for an empty default value if you're comfortable with that

[atextor]

Looks good to me!