Increased load time when viewing blog posts

Issue Summary

Increased load time when viewing blog posts on Confluence instances with large number of blog posts over several years (3.5k blog posts over 14 years).

This is reproducible on Data Center: yes

Steps to Reproduce

1. Install a Confluence version mentioned in the affected versions
2. Find a dataset or create a space with a lot of blogposts (e.g. 3000 blog posts over 10+ years)
3. Navigate to any blogpost

Expected Results

Blog post loads as fast as other pages.

Actual Results

~6-10 second delay when loading blog post page. `PageManager.getBlogPosts()` is executed several times:

[5711.1ms] [count: 14, avg: 407.9ms] - PageManager.getBlogPosts() 

Workaround

Currently there is no known workaround for this behavior. A workaround will be added here when available