[13pt] Add benchmark data for NWS AHPS sites in Alaska

[mluck]

With the addition of southern Alaska to FIM processing (#1106), we want to add validation data for the NWS AHPS sites there. Those site lids include MNDA2, SKLA2, and SXRA2.

[mluck]

There is a script in the repo archive (https://github.com/NOAA-OWP/inundation-mapping/blob/eed7206723faefb29bdb3a6f95a1ce13314ee9e8/tools/preprocess_ahps_nws.py) that was presumably used to create the CONUS NWS benchmark data, although this script doesn't exist in the current repo and is not currently runnable.

[CarsonPruitt-NOAA]

The new benchmark data should probably be in the Alaska projection.