attributes missing when creating S1* file in radar coordinates

[falkamelung]

This is a MiaplyPy issue, because the creation of a S1* file in radar coordinates is only relevant for MiaplyPy data.

If I say mintpy.save.hdfEos5.subset = yes I get this error:

save_hdfeos5.py timeseries_demErr.h5 --tc temporalCoherence.h5 --asc avgSpatialCoh.h5 -m  ../maskPS.h5 -g inputs/geometryRadar.h5 -t smallbaselineApp.cfg --suffix PS $update
read options from template file: smallbaselineApp.cfg
Input file is not geocoded, no data_footprint without X/Y_FIRST/STEP info.
## UNAVCO Metadata:
-----------------------------------------
  atmos_correct_method      None
  beam_mode                 IW
  beam_swath                3
  first_date                2015-09-21
  first_frame               81
  flight_direction          A
  history                   2022-08-02
  last_date                 2021-11-12
  last_frame                82
  look_direction            R
  mission                   S1
  polarization              VV
  post_processing_method    MintPy
  prf                       1685.817302492702
  processing_dem            Unknown
  processing_software       isce
  processing_type           LOS_TIMESERIES
  relative_orbit            48
  scene_footprint           POLYGON((-80.23931223791634 25.40699917238294,-80.37648662818698 26.089217886949804,-79.58717570767169 26.215613743859954,-79.45471838400576 25.53393687281258,-80.23931223791634 25.40699917238294))
  unwrap_method             Unknown
  wavelength                0.05546576

-----------------------------------------
Subset mode is enabled, put subset range info in output filename.
Traceback (most recent call last):
  File "/work2/05861/tg851601/stampede2/codet/rsmas_insar/sources/MintPy/mintpy/save_hdfeos5.py", line 487, in <module>
    main(sys.argv[1:])
  File "/work2/05861/tg851601/stampede2/codet/rsmas_insar/sources/MintPy/mintpy/save_hdfeos5.py", line 469, in main
    out_file = get_output_filename(metadata=meta,
  File "/work2/05861/tg851601/stampede2/codet/rsmas_insar/sources/MintPy/mintpy/save_hdfeos5.py", line 274, in get_output_filename
    lat1 = float(metadata['Y_FIRST'])
KeyError: 'Y_FIRST'

It should use the relevant attributes from geometryRadar.h5. Alfredo has sort-of fixed similar issues in the insarmaps scripts when an S1* files is in radar coordinate. I can put a example dataset on Jetstream if you need.