[fix #1029] Add check for user dico in TelemacCas

Add a new method to check for user specified dictionary in CAS file. It prevents a TelemacException during computation initialisation caused by a keyword check against default dictionnary instead of user specified one.

Before

[...]
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... processing the steering file
  ~> Checking keyword/rubrique coherence
Traceback (most recent call last):
  File "/opt/telemac-mascaret/v8p4r1/scripts/python3/telemac2d.py", line 7, in <module>
    main('telemac2d')
  File "/slurm/opt/telemac-mascaret/v8p4r1/scripts/python3/runcode.py", line 288, in main
    run_study(cas_file, code_name, options)
  File "/slurm/opt/telemac-mascaret/v8p4r1/scripts/python3/execution/run_cas.py", line 163, in run_study
    my_study = Study(
  File "/slurm/opt/telemac-mascaret/v8p4r1/scripts/python3/execution/study.py", line 130, in __init__
    self.cas = TelemacCas(self.steering_file, self.dico_file)
  File "/slurm/opt/telemac-mascaret/v8p4r1/scripts/python3/execution/telemac_cas.py", line 110, in __init__
    self._check_content()
  File "/slurm/opt/telemac-mascaret/v8p4r1/scripts/python3/execution/telemac_cas.py", line 268, in _check_content
    raise TelemacException(
utils.exceptions.TelemacException: Unknown keyword NUMBER OF BRIDGES in steering file T2D_steering.cas

After

[...]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


... processing the steering file
  ~> Checking keyword/rubrique coherence
  ~> User dictionary detected
  ~> Checking keyword/rubrique coherence

... checking parallelisation

... handling temporary directories
         copying: T2D_steering.cas -> /slurm/projects/TELEMAC/22RED008/T2D_BridgeModule-main/examples/example1/T2D_steering.cas_2024-06-28-10h59min36s/T2DCAS
         copying: telemac2d_mod.dico -> /slurm/projects/TELEMAC/22RED008/T2D_BridgeModule-main/examples/example1/T2D_steering.cas_2024-06-28-10h59min36s/T2DDICO
         copying: bridges.i2s -> /slurm/projects/TELEMAC/22RED008/T2D_BridgeModule-main/examples/example1/T2D_steering.cas_2024-06-28-10h59min36s/BRILOC
         copying: bridges_cut.i2s -> /slurm/projects/TELEMAC/22RED008/T2D_BridgeModule-main/examples/example1/T2D_steering.cas_2024-06-28-10h59min36s/BRISEC
         copying: Mesh.slf -> /slurm/projects/TELEMAC/22RED008/T2D_BridgeModule-main/examples/example1/T2D_steering.cas_2024-06-28-10h59min36s/T2DGEO
         copying: BC.cli -> /slurm/projects/TELEMAC/22RED008/T2D_BridgeModule-main/examples/example1/T2D_steering.cas_2024-06-28-10h59min36s/T2DCLI
         copying: fluxlines.txt -> /slurm/projects/TELEMAC/22RED008/T2D_BridgeModule-main/examples/example1/T2D_steering.cas_2024-06-28-10h59min36s/T2DFLX
        ignoring: telemac2d_mod.dico /slurm/projects/TELEMAC/22RED008/T2D_BridgeModule-main/examples/example1/T2D_steering.cas_2024-06-28-10h59min36s/T2DDICO

... checking the executable
  > compiling objs
         compiling: a0_bief_def.f ... completed
         compiling: a1_declarations_telemac2d.f ... completed
         compiling: a2_interface_telemac2d.f ... completed
         compiling: a3_lecdon_telemac2d.f ... completed
         compiling: a4_telemac2d_init.F ... completed
         compiling: a5_deall_telemac2d.f ... completed
         compiling: bbuilder.f ... completed
         compiling: flusec_t2d.f ... completed
         compiling: prosou.f ... completed
         created: out_user_fortran


Running your simulation(s) :
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