To formalize they are now XML-compliant (with some asterisks.)
Also to help syntax highlighters work on them to make their content more
readable.
Also:
- Delete empty comment decorations.
- GHA/checksrc: simplify XML check.
- runtests: fail to load test data with XML prolog missing.
Follow-up to bfe6eb1c06#19927
Follow-up to 87ba80a6dfCloses#19946
missing CRs and modified %hostip
lib556/test556: use a real HTTP version to make test reuse more convenient
make sure the weekday in Date headers matches the date
test61: replace stray "^M" (5e 4d) at the end of a cookie with a '^M' (0d)
Gets the test working with external proxies like Privoxy again.
Closes#6463