Handle case of no inner for cards

[lamATnginx]

Proposed changes

To better handle closing tags on card shortcode such as {{<card ... />}}, the following need to be changed -

• Fix whitespace issues resulting in the following when rendered:
  

• Better handle case where there is no .Inner due to the closing tag. This results in more centered header as seen below:

  Before:
  

  After:
  

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING document
• If applicable, I have added tests that prove my fix is effective or that my feature works
• If applicable, I have checked that any relevant tests pass after adding my changes
• I have updated any relevant documentation (README.md and CHANGELOG.md)

[github-actions]

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