Small fix for app snapshots

[maala-nfi]

Since _lava_media_info.updated_at is the second to last column in the result of the query used in function lava_get_full_media_info, the list item used for variable last_modified_date should be updated from -1 to -2. (The query was updated in commit 28ea00e.)

[JamesHabben]

Good catch on updated_at moving positions.

Could we avoid the positional index here and use the row column name instead?

[maala-nfi]

Could we avoid the positional index here and use the row column name instead?

Yes! That would be even better.
I tested it and committed the change.