[agrum] clang-tidy fixes

12 jobs from internal/clang-tidy in 2 minutes and 6 seconds (queued for 1 second)
Status Job ID Name Coverage
  Agrum
passed #56949318
gcc-5 python3 linux
linux_aGrUM_build

00:00:34

passed #56949319
python3 macos
macos_aGrUM_build

00:00:58

canceled #56949320
conda windows
windows_aGrUM_build

00:02:04

 
  Pyagrum
canceled #56949321
gcc-5 python3 linux
linux_pyAgrum_build

canceled #56949323
python3 macos
macos_pyAgrum_build

canceled #56949326
conda windows
windows_pyAgrum_build

 
  Agrum Test
canceled #56949328
gcc-5 python3 linux
linux_aGrUM_test

canceled #56949330
python3 macos
macos_aGrUM_test

canceled #56949331
conda windows
windows_aGrUM_test

 
  Pyagrum Test
canceled #56949332
gcc-5 python3 linux
linux_pyAgrum_test

canceled #56949333
python3 macos
macos_pyAgrum_test

canceled #56949334
conda windows
windows_pyAgrum_test