Filename versioning on gracedb and interaction with gwcelery

This is a quality of life improvement suggestion/request. It might head off mistakes by the PE rota experts when issuing update GCN notices.

When creating GCN notice updates I have run into the problem that the drop-down menus at https://emfollow.ligo.caltech.edu/gwcelery/ don't reflect all the file versions. This can cause an error (and I made this error for S240922df) when trying to select the most up-to-date file for the notice. It seems like the issue may be that the drop-down is limited to two entries. Screenshots:

Note the correct files to use are em_bright.json,2 and gstlal.p_astro.json,1.

Meanwhile the main gracedb page does not give the file versions in the links for em_bright and pastro values. Instead all such links redirect to the most up-to-date file contents (without a version number in the URL) even when the link is under an old image with contradicting data. The result is that there can be confusion about which file version to use in the GCN update.

It might be nicer to have the filenames listed on the gracedb page have their version number and have the drop-down menus list all filename options.

In any case @alexander.pace has provided a good fix, which is to take the file versions from the corresponding https://gracedb.ligo.org/superevents/<S240922df/<SID>/files/ page. We will direct people to look at this as the source of truth in the future, hence why this is just a quality of life/UI issue.