Added Lambda1520 PDG code to PhysicsConstants.h

[hkoley]

Added PDG code according to new PYTHIA PDG convention

[github-actions]

REQUEST FOR PRODUCTION RELEASES:
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The following labels are available
async-2023-pbpb-apass4
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async-2024-PbPb-apass1
async-2024-ppRef-apass1
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[alibuild]

Error while checking build/O2/fullCI_slc9 for 26b3a49 at 2025-07-22 12:34:

## sw/BUILD/O2-latest/log
/sw/SOURCES/O2/14377-slc9_x86-64/0/Common/Constants/include/CommonConstants/PhysicsConstants.h:201:18: error: redefinition of 'constexpr const double o2::constants::physics::MassLambda1520'
/sw/SOURCES/O2/14377-slc9_x86-64/0/Common/Constants/include/CommonConstants/PhysicsConstants.h:201:18: error: redefinition of 'constexpr const double o2::constants::physics::MassLambda1520'
/sw/SOURCES/O2/14377-slc9_x86-64/0/Common/Constants/include/CommonConstants/PhysicsConstants.h:201:18: error: redefinition of 'constexpr const double o2::constants::physics::MassLambda1520'
ninja: build stopped: subcommand failed.

Full log here.

[vkucera]

@shahor02 Looks ready to merge from my side.