Update AnnotatedImageBlock to use LinkBlock

[danielfmiranda]

Description

Related PRs/issues: #12480, TP1-804

This PR implements the following changes:

• New Class LinkWithoutLabelBlock: Derived from LinkBlock, it omits the required label field, allowing usage where a label is not necessary, such as in AnnotatedImageBlock where the "caption" serves as the label.
• captionURL charField Replacement: Replaces the captionURL char field with caption_url using LinkWithoutLabelBlock, wrapped in a ListBlock to make it optional.
• Template Update: Updates the annotated_image_block.html template to account for the new field.
• Streamfield Provider Update: Modifies the factory method for AnnotatedImageBlock to include a link value when created via the streamfield provider.
• Data Migrations: Adds new caption_url field, migrates existing data, and deletes the old captionURL field.
• Test Updates: Adjusts test_block_type_report.py to accommodate the new LinkWithoutLabelBlock field.

┆Issue is synchronized with this Jira Story

Screenshots

Before (with CharBlock):

After (with LinkWithoutLabelBlock):

[robdivincenzo]

LGTM @danielfmiranda! Thanks for taking point on this first PR for the epic

[data-sync-user]

➤ Simon Acosta Torres commented:

PR merged.