Docs: add Open OnDemand/OnDemand Loop integration

[pdurbin]

What this PR does / why we need it:

This PR adds Open OnDemand/OnDemand Loop to

• the list of integrations (under both "Getting Data In" and "Analysis and Computation")
• the inventory of external tools
• the list of open source applications (under Ruby, a new heading)

Which issue(s) this PR closes:

• Closes Open OnDemand/OnDemand Loop as an external tool in the guides #11768

Special notes for your reviewer:

Here are the pages to review:

• https://dataverse-guide--11769.org.readthedocs.build/en/11769/admin/integrations.html#open-ondemand
• https://dataverse-guide--11769.org.readthedocs.build/en/11769/admin/integrations.html#ood-download
• https://dataverse-guide--11769.org.readthedocs.build/en/11769/admin/external-tools.html#inventory-of-external-tools
• https://dataverse-guide--11769.org.readthedocs.build/en/11769/api/apps.html#open-ondemand-loop

Is there a release notes update needed for this change?:

Yes, included.

[ofahimIQSS]

Although not a part of the change in this PR, on the last preview URL on the description under OpenScholar:

https://dataverse-guide--11769.org.readthedocs.build/en/11769/api/apps.html#open-ondemand-loop

https://github.com/openscholar/openscholar/tree/SCHOLAR-3.x/openscholar/modules/os_features/os_dataverse --- this url leads to github 404 page.

[ofahimIQSS]

created #11797 to track broken link issue, merging this.

I will test this later on as my FASRC account request was rejected.