[PWGEM] add additional max. mass pair cut to reduce number of events

[Steffimro]

No description provided.

[github-actions]

O2 linter results: ❌ 3 errors, ⚠️ 20 warnings, 🔕 0 disabled

[alibuild]

Error while checking build/O2Physics/code-check for 8479455 at 2026-08-24 14:05:

## sw/BUILD/O2Physics-code-check-latest/log
--
========== List of issues found ==========
++ echo 'Found 2 errors and 0 warnings.'
Found 2 errors and 0 warnings.
++ [[ 2 -gt 0 ]]
++ cat /sw/BUILD/9739c3739710c978669f9152fb58eda329b821c8/O2Physics-code-check/errors.txt
PWGEM/Dilepton/TableProducer/filterEoI.cxx:32:1: error: included header Vector4D.h is not used directly [misc-include-cleaner,-warnings-as-errors]
PWGEM/Dilepton/TableProducer/filterEoI.cxx:126:27: error: no header providing "ROOT::Math::PtEtaPhiMVector" is directly included [misc-include-cleaner,-warnings-as-errors]
++ [[ 0 -gt 0 ]]
++ [[ 2 -gt 0 ]]
++ exit 1
--

Full log here.