remove duplicated LA message

[cbellot000]

when ANSYS_DPF_ACCEPT_LA is not accepted, the error message appears 4times:

Dpf initialization encountered an error: DPF error - licensing failure: dpf core function call; DPF Preview License Agreement terms must be accepted using the ANSYS_DPF_ACCEPT_LA environment variable set to Y. Fore more information about DPF Preview License Agreement terms, see https://dpf.docs.pyansys.com/version/stable/user_guide/getting_started_with_dpf_server.html#dpf-preview-license-agreement.

terminate called after throwing an instance of 'ansys::dpf::DpfException'

  what():  DPF error - runtime error: dpf core function call; DPF Preview License Agreement terms must be accepted using the ANSYS_DPF_ACCEPT_LA environment variable set to Y. Fore more information about DPF Preview License Agreement terms, see https://dpf.docs.pyansys.com/version/stable/user_guide/getting_started_with_dpf_server.html#dpf-preview-license-agreement.

Dpf initialization encountered an error: DPF error - licensing failure: dpf core function call; DPF Preview License Agreement terms must be accepted using the ANSYS_DPF_ACCEPT_LA environment variable set to Y. Fore more information about DPF Preview License Agreement terms, see https://dpf.docs.pyansys.com/version/stable/user_guide/getting_started_with_dpf_server.html#dpf-preview-license-agreement.

terminate called after throwing an instance of 'ansys::dpf::DpfException'

  what():  DPF error - runtime error: dpf core function call; DPF Preview License Agreement terms must be accepted using the ANSYS_DPF_ACCEPT_LA environment variable set to Y. Fore more information about DPF Preview License Agreement terms, see https://dpf.docs.pyansys.com/version/stable/user_guide/getting_started_with_dpf_server.html#dpf-preview-license-agreement.

One duplicate is due to wrong usage of LOG error, see doc for good practices.
One duplicate is due to wrong error handling server side (fixed in server PR)

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.14%. Comparing base (939653b) to head (ec2e9bf).
Report is 8 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1523      +/-   ##
==========================================
- Coverage   84.46%   82.14%   -2.32%     
==========================================
  Files          82       82              
  Lines        9673     9650      -23     
==========================================
- Hits         8170     7927     -243     
- Misses       1503     1723     +220