Isolate feed builds

[maneesha]

Right now, if one feed fails, the entire process fails. Either in the Makefile or GitHub Actions, this should be set up so that we are alerted that feed fails, but the remaining feeds continue.

[zkamvar]

This has been partially addressed in #73 by separating the builds into separate steps, but a single failing check on one of the other steps could make this one fail as well.

In #62 I created the EXIT_STATUS environment variable such that failures in our lesson data could be caught and sent up to us. In that PR, I added a fine-grain catch for a specific edge case because I knew the data would go through fine and what the fix was.

In #73, I added a catch for that particular process by using the || BASH operator to shortcut in case of an error, recording to EXIT_STATUS and moving on.

We could do the same for the other processes, but it might be a good idea to have all of these processes set EXIT_STATUS + 1 for each failure so that we know how many processes fail by the status number.