Re-introduce older 0.22.x releases in the past releases section

Summary:
0.22.5 and earlier were removed in D8290 in order to side-step
limitations where Liquid does not provide good pattern matching
capabilities. This patch adds those older releases back with a workaround.

Test Plan:
Spoof the next version to aid testing:

./scripts/fetch_documentation.sh
cd abc_md_docs
cp doc/release-notes/release-notes-0.22.6.md doc/release-notes/release-notes-0.22.7.md
cp doc/release-notes/release-notes-0.22.6.page.md doc/release-notes/release-notes-0.22.7.page.md

Add an entry in _data/github-releases.json for version 0.22.7, then:

make serve

Navigate to http://127.0.0.1:4000/releases/

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D8313