Fixes for lcg104

• add fmtlib customization for Muon::TileID needed to build Run2Support and Boole with LCG 103a
• fix compilation errors with C++20

Note: this is part of a pool of related (not interdependent) MRs: !400 (merged), LHCb!4143 (merged), Run2Support!46 (merged), Boole!483 (merged), Rec!3449 (merged), Alignment!388 (merged)

See also https://its.cern.ch/jira/projects/LHCBPS/issues/LHCBPS-1912

Commit d154cfe6 can be dropped when we drop support for fmtlib 8.