Enhance adjust-pages patch logic to target only one version; add patches

[chalin]

• Adjusts adjust-pages.pl, the script used to prepare spec and other content-module pages for use by our Hugo site build
• Determines whether to apply a patch based on the pinned submodule version
• Allows us to apply patches to a specific version only, or dev versions of a specific version. This was we can include forward-coming patches to the main branch without worry of them being applied.
• Adds the semconv patch recently added to DRAFT Update semantic conventions to unreleased v1.39.0-dev #8311

There are no changes to the generated site files (other than the timestamp):

$ (cd public && git diff -bw --ignore-blank-lines) | grep ^diff | head
diff --git a/site/index.html b/site/index.html

/cc @vitorvasc