[5.1] Change item type to stdClass

[laoneo]

Followup of #42717, to change the type of items in the views to \stdClass.

[ceford]

I have tested this item ✅ successfully on 1126544

Not sure about my test. I am using the Testing Sample Data and went through almost all of the views mentioned in the diffs - no problems with the patch applied.

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[viocassel]

I have tested this item ✅ successfully on 1126544

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[richard67]

RTC

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[bembelimen]

Thx