build and sub in the static overview map into background section

[NewGraphEnvironment]

As per instructions mis-placed into https://github.com/NewGraphEnvironment/fish_passage_peace_2022_reporting/issues/10

Use the updated fishpassage_skeena_2022 map on mergin, be sure to sync changes from generating Bulkley map before beginning

• [x] duplicate composer of map used for bulkley 2022,
• [x] use watershed group layer already good to go for bulk, morr, kisp and zymo (leave bulk in there even though no sites in there yet)
• [ ] name png output the same as bulkley and save direct from mergin to this repo fig file.
• [ ] use export png resolution of 200px so not a huge file
• [x] Lock out layers and styles in map object in composer when done so map won't change when map view changed.
• [x] sync to mergin when draft completed

[Mateo9569]

As seen in the commit mentioned above, I named the file fishpassage_overview. Hope that was ok, I thought that would be easier so we can call the same name in future projects. The output file is around 5mb, similar to bulkley.