[EGM] xml.gz to root conversion for photons

[swagata87]

Converting xml files to root files to speed things up.
This is a follow-up of cms-sw/cmssw#38339

[cmsbuild]

A new Pull Request was created by @swagata87 (Swagata Mukherjee) for branch master.

@smuzaffar, @aandvalenzuela, @iarspider, @clacaputo, @cmsbuild, @jpata can you please review it and eventually sign? Thanks.
@Sam-Harper, @jainshilpi, @valsdav, @lgray, @sobhatta, @afiqaize, @wrtabb, @varuns23, @ram1123 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

[clacaputo]

@cmsbuild please test with cms-sw/cmssw#38556

[cmsbuild]

+1

Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-37e895/26207/summary.html
COMMIT: bf13101
CMSSW: CMSSW_12_5_X_2022-07-13-1100/el8_amd64_gcc10
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week1/cms-data/RecoEgamma-PhotonIdentification/12/26207/install.sh to create a dev area with all the needed externals and cmssw changes.

The following merge commits were also included on top of IB + this PR after doing git cms-merge-topic:

• @bsunanda Run3-gex136E Try too remove compilation warnings in PhysicsTools/PatAlgos cms-sw/cmssw#38670

You can see more details here:
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-37e895/26207/git-recent-commits.json
https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-37e895/26207/git-merge-result

Comparison Summary

Summary:

• No significant changes to the logs found
• Reco comparison results: 4 differences found in the comparisons
• DQMHistoTests: Total files compared: 50
• DQMHistoTests: Total histograms compared: 3653966
• DQMHistoTests: Total failures: 13
• DQMHistoTests: Total nulls: 1
• DQMHistoTests: Total successes: 3653930
• DQMHistoTests: Total skipped: 22
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.004 KiB( 49 files compared)
• DQMHistoSizes: changed ( 312.0 ): 0.004 KiB MessageLogger/Warnings
• Checked 208 log files, 45 edm output root files, 50 DQM output files
• TriggerResults: no differences found

[qliphy]

+1
tested with cms-sw/cmssw#38556

[qliphy]

merge