Fix CosmoSkyMed ImageMetadataInterface

Summary

• Test that the product is CosmoSkyMed before trying to open the hdf5 subdatasets.
• Remove unused code

Rationale

Currently, opening an image that is not a CosmoSkyMed product leads to the following logs:

HDF5-DIAG: Error detected in HDF5 (1.10.1) thread 0:
  #000: /home/cedric/OTB/Superbuild/HDF5/src/HDF5/src/H5F.c line 586 in H5Fopen(): unable to open file
    major: File accessibilty
    minor: Unable to open file
  #001: /home/cedric/OTB/Superbuild/HDF5/src/HDF5/src/H5Fint.c line 1384 in H5F_open(): unable to read superblock
    major: File accessibilty
    minor: Read failed
  #002: /home/cedric/OTB/Superbuild/HDF5/src/HDF5/src/H5Fsuper.c line 360 in H5F__super_read(): file signature not found
    major: File accessibilty
    minor: Not an HDF5 file

(note that this does not cause a crash)

because CosmoImageMetadataInterface::Parse tries to open hdf5 subdatasets before determining if the product is or is not a Cosmo product.

This is a regression introduced in !761 (merged)

Copyright

The copyright owner is CNES and has signed the ORFEO ToolBox Contributor License Agreement.

---

Check before merging:

• All discussions are resolved
• At least 2 👍 votes from core developers, no 👎 vote.
• The feature branch is (reasonably) up-to-date with the base branch
• Dashboard is green
• Copyright owner has signed the ORFEO ToolBox Contributor License Agreement
• Optionally, run git diff develop... -U0 --no-color | clang-format-diff.py -p1 -i on latest changes and commit