Add tool to fix missing "source" links in our documentation

[potiuk]

The problem (fixed in #24386) with broken links was that
the autoapi-generated source html were either exluded
(via example_dags/** exclusion) or not included (system_tests)
when the documentation was generated.

We cannot easily re-add and regenerated all those autoapi sources
so instead the fix is to replace all the links to autoapi sources
with corresponding links to raw github sources. We can easily do
that using tags of providers and link to specific tagged versions
of those example dags and this is the best we can do now.

The #24386 brings back linking to autoapi-generated html pages.

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[ashb]

Do we need this in the repo? Once we've run it we don't need it anymore do we?

[potiuk]

Do we need this in the repo? Once we've run it we don't need it anymore do we?

It's good for reference to find it. Also @josh-fell used them later as a reference and good "source" of what has been fixed in building astronomer index. I find it useful to keep it there, in case someone wants to have similar fix in the future. First time it took me quite some time to figure out how to do, second time it was couple of minutes precisely because I could find it easily how it was done before.

[potiuk]

Also those are useful in case somoen finds a problem with such mass-updated changes like you did apache/airflow-site#613 (comment) @ashb - (I will look into that).

If we've already merged the change and if there is a mistake that would lead to wrong corrections of the link, the easiest way to find why and fix it is to have reference to the script that was used. Otherwise any diagnosis and fix by anyone else but me hoping to still keep the script around would be much more difficult.

So say this is a way to not loose time with any followups.

[potiuk]

The tool is optimized now

[potiuk]

Applied the latest fix @ashb .

I'd very much like to keep those scripts in, actually (as explained - there might be errors we missed during the review, the apache/airflow-site#613 has reference to this PR and scripts used to fix the problems so we have an easy way to revert and re-run the fixes in case we find out that we need to. The interlinking in PRs make it permanent trace to all such changes for anyone who might want to wonder where it came from (and might even fix it if I am not around).

[potiuk]

@ashb ?

[potiuk]

I would love to get it in (just for tracking of what has been done).

[potiuk]

Would love to merge this one - we have one more case that might need fixes and it would be great to get this one as a base.