[DPG] Adding ITS task for impact parameter studies

[scattaru]

Dear all,
I have added a task related to impact parameter studies to the ITS Working Group.

Let me know for any comments,
Cheers,
Samuele

[github-actions]

O2 linter results: ❌ 48 errors, ⚠️ 0 warnings, 🔕 0 disabled

[alibuild]

Error while checking build/O2Physics/o2 for 10f63f7 at 2025-06-04 11:16:

## sw/BUILD/O2Physics-latest/log
/sw/SOURCES/O2Physics/11401-slc9_x86-64/0/DPG/Tasks/ITS/itsImpParStudies.cxx:356:10: error: variable 'PDGtoIndex' set but not used [-Werror=unused-but-set-variable]
/sw/SOURCES/O2Physics/11401-slc9_x86-64/0/DPG/Tasks/ITS/itsImpParStudies.cxx:356:10: error: variable 'PDGtoIndex' set but not used [-Werror=unused-but-set-variable]
ninja: build stopped: subcommand failed.

Full log here.

[scattaru]

Dear @alcaliva, @chiarazampolli, @catalinristea, I see that the auto merging is enabled but I don't know why the merging is still blocked. Probably it is necessary to first approve the PR in order to get it merged

[alcaliva]

Merged.
Try to fix the linter at the next opportunity