Add meta tags in next starter

[rajeshreeputra]

Motivation: Currently there is no option to include drupal metatags in next page template, in this PR added meta to slug so it will start rendering the tags coming from Drupal application.

[harumijang]

@rajeshreeputra Can you share the steps on how to add metatags in ACMS so I can test this?

[rajeshreeputra]

• composer create-project acquia/drupal-recommended-project project && cd project
• ./vendor/bin/acms acms:install acquia_cms_headless
• select yes to "Do you want to enable demo content (yes/no) ?"
• select yes to "Would you like to preconfigure a next.js site (yes/no) ?"
• Now site will be installed with ACMS headless starter
• Now create nextjs application
• npx create-next-app -e https://github.com/rajeshreeputra/next-acms/tree/patch-1/starters/basic-starter
• follow steps from here, not the first step.
• Now visit nextjs application
• visit any content, and inspect element, and verify the metatags now available.😊

[chandan-singh7929]

@apathak18 - As discussed, please create separate ticket to update logic of keywords meta tags, its having value like ="," if there's no keyword assigned to the content.

[apathak18]

On content page, the output is like as below screenshot: