Closes #5274: Adds margin 0 override to entity reference fields

[zsaenz]

Closes #5274 Entity Reference Fields have extra margin-bottom #5274

Fixes a style issue in Opportunity Content Type, found here: #5182

Description

When using Entity Reference fields, Barrio Core has a style issue of extra bottom margin. This means fields of type Entity Reference behave differently than fields of other types like Text Fields, and can't be aligned to match the style settings. This is most noticed when using smaller In-line labels for the fields.

This is meant as both a follow up to fix the style issue specifically found in Opportunities, as well as help future editors style their customized Taxonomy references.

Release notes

Related issues

How to test

-Create a new taxonomy, or add an existing one.
--Add terms to edit
-Create a new content type, or edit an existing one.
--Edit the content type's fields
--Add new references, and add a text field for testing
-Test the style and how it behaves with other content types. With Margin 0 it should behave like the other content types with label Above, label Inline, and Custom Labels using Field Groups.
-Test with other entity reference fields, including az_core items and other content types.

Types of changes

Arizona Quickstart (install profile, custom modules, custom theme)

• Patch release changes
  • Bug fix
  • Accessibility, performance, or security improvement
  • Critical institutional link or brand change
  • Adding experimental module
  • Update experimental module
• Minor release changes
  • New feature
  • Breaking or visual change to existing behavior
  • Upgrade experimental module to stable
  • Enable existing module by default or database update
  • Non-critical brand change
  • New internal API or API improvement with backwards compatibility
  • Risky or disruptive cleanup to comply with coding standards
  • High-risk or disruptive change (requires upgrade path, risks regression, etc.)
• Other or unknown
  • Other or unknown

Drupal core

• Patch release changes
  • Security update
  • Patch level release (non-security bug-fix release)
  • Patch removal that's no longer necessary
• Minor release changes
  • Major or minor level update
• Other or unknown
  • Other or unknown

Drupal contrib projects

• Patch release changes
  • Security update
  • Patch or minor level update
  • Add new module
  • Patch removal that's no longer necessary
• Minor release changes
  • Major level update
• Other or unknown
  • Other or unknown

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.
• My change requires release notes.