Include last-modified in metadata

[herzog31]

• Include new last-modified field in metadata sheet to return correct last-modified header for all products.
• Minor fixes in open graph metatags.

Test URLs:

• Before: https://main--aem-boilerplate-commerce--hlxsites.aem.live/
• After:
  • https://last-modified--aem-boilerplate-commerce--hlxsites.aem.live/
  • https://last-modified--aem-boilerplate-commerce--hlxsites.aem.live/products/crown-summit-backpack/24-MB03

[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

* [a049a1d](https://github.com/hlxsites/aem-boilerplate-commerce/commit/a049a1d6064d681d09b73a6500ea06547705bb7e) :arrows_counterclockwise: (latest) * [c2f3a9f](https://github.com/hlxsites/aem-boilerplate-commerce/commit/c2f3a9fd9d0b012a35edb6905f06d437a2f8f9c7) :white_check_mark:

[aem-code-sync[bot]]

	Page	Scores	Audits	Google
:iphone:	/
:desktop_computer:	/
:iphone:	/products/crown-summit-backpack/24-MB03
:desktop_computer:	/products/crown-summit-backpack/24-MB03