This change replaces outdated internal base64 encoding and decoding calls with their modern equivalents across several Odoo areas. It helps keep the platform compatible with current and future Python versions without changing business workflows or visible features.

PEP-594 is deprecating a bunch of modules/functions, as part of the
related cleanup, we also remove long deprecated functions. Unlike the
`encodestring` and `decodestring` suggest, those two functions do not
support string inputs but only work on bytes-like objects.

The two functions got deprecated in python3.1 and got replaced by the
`encodebytes` and `decodebytes` functions.

Task: 2003936

This change updates how users mark lunch products as favorites, moving the action to Odoo's standard data handling approach. The visible lunch ordering experience should stay the same, while the underlying implementation becomes easier to maintain and test.

Description of the issue/feature this PR addresses:

Current behavior before PR:

Desired behavior after PR is merged:




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This update replaces outdated test assertions with their current equivalents across several Odoo Enterprise modules. It helps keep the automated test suite compatible with newer Python standards without changing customer-facing behavior.

Task: 2003936