USF-1510 DEMO: Cart Summary has a Footer Slot

[anthoula]

Please always provide the GitHub issue(s) your PR is for, as well as test URLs where your change can be observed (before and after):

Fix #

Test URLs:

• Before: https://develop--aem-boilerplate-commerce--hlxsites.aem.live/
• After: https://USF-1510-demo--aem-boilerplate-commerce--hlxsites.aem.live/

[aem-code-sync[bot]]

Hello, I'm the AEM Code Sync Bot and I will run some actions to deploy your branch and validate page speed. In case there are problems, just click a checkbox below to rerun the respective action.

• [ ] Re-run PSI checks
• [ ] Re-sync branch

Commits

* [b94f6ab](https://github.com/hlxsites/aem-boilerplate-commerce/commit/b94f6abb9e368d05e7febd2e28dbbe37f6faa1a4) :white_check_mark: (latest) * [b774f87](https://github.com/hlxsites/aem-boilerplate-commerce/commit/b774f874cad2840d3cbf788b9cefef79d4975dad) :white_check_mark: * [8180cb5](https://github.com/hlxsites/aem-boilerplate-commerce/commit/8180cb5d7400128e506704cf868183275ec08eae) :white_check_mark:

[aem-code-sync[bot]]

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