Replace annotation of field type plugin with attribute

Problem/Motivation

From Drupal 10.3 on, field type plugins should use attributes instead of a plugin annotations. See the following for more information:

• 📌 [PP-1] Convert FieldType plugin discovery to attributes Postponed
• https://www.drupal.org/node/3229001 →
• https://www.drupal.org/node/3395575 →

So this should be changed for view_mode_switch field type plugin once Drupal 10.2.x is not supported by the module anymore.

Proposed resolution

• Replace view_mode_switch field type plugin annotation with Drupal\Core\Field\Attribute\FieldType attribute

Remaining tasks

• Create issue fork and MR to fix this issue

User interface changes

n/a

API changes

• view_mode_switch field type plugin will only be found by attribute discovery of field type plugins anymore

Data model changes

n/a