[124X (backport)] Introduce era with CKF pixelLessStep: backport of #38437

[mmasciov]

PR description:

This PR introduces a new era modifier where mkFit is disabled for PixelLessStep.
This is meant as a (temporary) fix for the inefficiency previously reported by BPH (https://indico.cern.ch/event/1166179/#3-feedback-from-bph-on-mkfit).

This is a backport of PR #38437.

PR validation:

As described in https://indico.cern.ch/event/1169208/#5-mkfit-cross-check-of-ineffic

[cmsbuild]

A new Pull Request was created by @mmasciov (Mario Masciovecchio) for CMSSW_12_4_X.

It involves the following packages:

• Configuration/Eras (operations)
• RecoTracker/IterativeTracking (reconstruction)

@perrotta, @clacaputo, @cmsbuild, @jpata, @qliphy, @fabiocos, @davidlange6 can you please review it and eventually sign? Thanks.
@fabiocos, @makortel, @felicepantaleo, @GiacomoSguazzoni, @JanFSchulte, @rovere, @VinInn, @Martin-Grunewald, @missirol, @ebrondol, @gpetruc, @mmusich, @mtosi, @dgulhan this is something you requested to watch as well.
@perrotta, @dpiparo, @qliphy you are the release manager for this.

cms-bot commands are listed here

[slava77]

@cmsbuild please test

[cmsbuild]

+1

Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-701ff9/25681/summary.html
COMMIT: b6b5392
CMSSW: CMSSW_12_4_X_2022-06-21-2300/el8_amd64_gcc10
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week0/cms-sw/cmssw/38450/25681/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• No significant changes to the logs found
• Reco comparison results: 0 differences found in the comparisons
• DQMHistoTests: Total files compared: 50
• DQMHistoTests: Total histograms compared: 3680359
• DQMHistoTests: Total failures: 2
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 3680335
• DQMHistoTests: Total skipped: 22
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 49 files compared)
• Checked 208 log files, 45 edm output root files, 50 DQM output files
• TriggerResults: no differences found

[jpata]

+reconstruction

• an exact backport of Introduce era with CKF pixelLessStep #38437
• the new era is not enabled, no reco changes by default

[perrotta]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_12_4_X IBs (tests are also fine) and once validation in the development release cycle CMSSW_12_5_X is complete. This pull request will be automatically merged.