fix(sec): Getting wrong final URL (from redirect) on presentation upload

[gustavotrott]

The function followRedirect was supposed to obtain the final URL when the first URL is a redirect link.
Turned out that it is always returning the first URL instead of follow the redirect and return the final URL.

This PR fix it.

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

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[paultrudel]

Everything looks good!

To test this I created a fake "rogue" server to redirect requests to.

I sent the following request
curl -s -X POST "https://bbb27.test/bigbluebutton/api/insertDocument?meetingID=random-4046244&checksum=ff787fe2c57abeee1f9c0e454f5c40632185ff54" --header "Content-Type: application/xml" --data '<modules> <module name="presentation"> <document current="true" downloadable="true" url="https://699e-129-222-187-237.ngrok-free.app/a.txt" filename="a.txt"/> </module> </modules>'

Viewing the requests to the server we see that the no redirect occurred after the final URL resolved which is what was needed.