chore: Update learning/ to fix translation problems in documentation

[Osalotioman]

In the documentation, multiple objects of a class were sometimes referred to using the style "MyClasss".
This PR updates these references to "MyClass objects" to fix translation problems in documentation.

This addresses part of #2067 for /learning.

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[qiskit-bot]

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One or more of the following people are relevant to this code:

• @christopherporter1

[abbycross]

Looks good to me! I want to be sure @christopherporter1 also reviews. Thanks!

[Osalotioman]

@abbycross can I look into another issue while awaiting review from @christopherporter1 since this is the last task of #2067 ?
Or it would be preferable to wait for this to get resolved first?

[abbycross]

Hi @Osalotioman, feel free to begin on another issue. I'll check in with @christopherporter1 and make sure we can get his sign-off on this one in the meantime. Many thanks!