[PWGCF] adding new analysis for multiharmonic correlations

[pengchon]

No description provided.

[github-actions]

O2 linter results: ❌ 0 errors, ⚠️ 35 warnings, 🔕 0 disabled

[vkucera]

Duplicate of #16403

[abilandz]

Duplicate of #16403

Dear @vkucera, that one was closed because the student didn't have a fork in sync with the master, and after making a commit, there were merging conflicts. Instead of wrestling with them, we decided to close that PR, sync the fork, and start over with a new and clean PR.

Your comments on 16403 are taken into account in this PR.

Thanks for your understanding!

[abilandz]

@pengchon : The compilation on MacOS-arm is failing due to

/Volumes/build/alice-ci-workdir/o2physics/sw/SOURCES/O2Physics/16457/0/PWGCF/MultiparticleCorrelations/Tasks/multiharmonicCorrelations.cxx:440:11: error: variable 'eta' set but not used [-Werror,-Wunused-but-set-variable] 440 | float eta = 0; | ^ 1 error generated.

Please can you push a new commit with this fix? This one is mandatory.

Also, see if you can fix the remaining 2 errors for O2linter quickly, otherwise address them in the next PR.

Thanks!