[5.2] Jooa11y plugin and schemaorg cache + hits conflicts

[pe7er]

When testing the PR #41956 I noticed another issue with the Page Cache Plugin and Preview + Accessibility Check in Article Edit.

Steps to reproduce the issue

• Enable the System - Page Cache Plugin (with browser cache off)
• Create a new Article
• Create a Menu Items of type "Single Article" and link to the new Article
• In "Maintenance: Clear Cache" /administrator/index.php?option=com_cache&view=cache clear all Cache
• Check "Maintenance: Clear Cache" for number of files
• Edit the Article
• Click on "Preview" and note the "Hits"
• Check "Maintenance: Clear Cache" for number of files
• Click on "Accessibility Check" and note the "Hits"
• Check "Maintenance: Clear Cache" for number of files

"Maintenance: Clear Cache" before Preview/Accessibility Check:

Preview/Accessibility Check:

Expected result

The Preview / Accessibility Check should not re-cache an already cached article.

Actual result

Preview

Cache after Preview

The Preview has created a cache file:
Now 2 Page and 2 Schemaorg cache files.

Accessibility Check

The Hit counter increased by 1 (from 16 to 17)

Cache after Accessibility Check

The Accessibility Check has created another cache file:
Now 3 Page and 3 Schemaorg cache files.

System information (as much as possible)

Additional comments