[CI] Script updates in support of semconv spec processing and testing

[chalin]

• Updates scripts in support of semconv spec processing, in particular Proposed semconv pre-release process semantic-conventions#1817
• Modifies scripts/content-modules/adjust-pages.pl so that we can compare versions given in the format of https://git-scm.com/docs/git-describe, such as v1.30.0-2-g81664494. In this way we can still get patches applied while we continue to work with semconv at HEAD (beyond the current version).
• Updates the front-matter normalization script, which was used to generate [editorial] Hugo front matter title and other fixes semantic-conventions#1820. There's room to simplify the script by embedding page-specific rewrite rules in the doc front matter, but that'll have to wait :).

/cc @trask