Bump datatables.net-fixedcolumns from 5.0.3 to 5.0.4

Bumps [datatables.net-fixedcolumns](https://github.com/DataTables/Dist-DataTables-FixedColumns) from 5.0.3 to 5.0.4.
- [Release notes](https://github.com/DataTables/Dist-DataTables-FixedColumns/releases)
- [Commits](https://github.com/DataTables/Dist-DataTables-FixedColumns/compare/5.0.3...5.0.4

)

---
updated-dependencies:
- dependency-name: datatables.net-fixedcolumns
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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