[Issue] Wrong method used to get attribute code in product comparison attribute list

This issue is automatically created based on existing pull request: magento/magento2#36929: Wrong method used to get attribute code in product comparison attribute list

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### Description (*)
Wrong method used to get attribute code in product comparison attribute list.

### Related Pull Requests

### Fixed Issues (if relevant)

### Manual testing scenarios (*)
1. Add product to comparison list
2. Go to comparison list
3. Inspect price line in attribute list
4. Element ID of price is now correct (product-price-1234-compare-list-price instead of product-price-1234-compare-list-)

### Questions or comments

### Contribution checklist (*)
- [ ] Pull request has a meaningful description of its purpose
- [ ] All commits are accompanied by meaningful commit messages
- [ ] All new or changed code is covered with unit/integration tests (if applicable)
- [ ] README.md files for modified modules are updated and included in the pull request if any [README.md predefined sections](https://github.com/magento/devdocs/wiki/Magento-module-README.md) require an update
- [ ] All automated tests passed successfully (all builds are green)