The previous code for the validator test was fairly messy due to
checking for both formats of the openapi url, one with
<variable_name> and the other with {variable_name}. To eliminate
this, we have standardized the format and restricted it to
{variable_name} as per the official format at:
https://swagger.io/docs/specification/describing-parameters.
For the PHP link, I just found an equivalent link that detailed
some well-known PHP security vulnerabilities.
As for the now defunct RequestBin, another instance is hosted
by another domain, so we can recommend using that for now.
The main cleanup here is to move the examples out of the bulleted
list, which was getting rendered in an ugly/confusing way.
I also removed some redundant text, fixed some typos, and changed
the wording a bit.
This reverts commit 5a1869901. I reviewed this change and decided not
to merge it yet, but then I did anyway <_< >_>, along with some others
in the same PR.
This should get test-documentation and test-help-documentation passing
again after we moved everything around in the last commit.
There are a lot more absolute links (generally in code comments) to
update, but they are lower-priority and can be done in a follow-up
pass.