fix(eclipse-mosquitto-mqtt): fix stringvalue mode regexp threshold

[sdepassio]

Description

Problème avec les options warning-regrexp et critical-regexp dans le mode string-value

Fixes CTOR-789

Type of change

• [x] Patch fixing an issue (non-breaking change)
• [ ] New functionality (non-breaking change)
• [ ] Functionality enhancement or optimization (non-breaking change)
• [ ] Breaking change (patch or feature) that might cause side effects breaking part of the Software

Checklist

• [x] I have followed the coding style guidelines provided by Centreon
• [ ] I have commented my code, especially hard-to-understand areas of the PR.
• [x] I have rebased my development branch on the base branch (develop).
• [ ] In case of a new plugin, I have created the new packaging directory accordingly.
• [ ] I have implemented automated tests related to my commits.
• [x] I have reviewed all the help messages in all the .pm files I have modified.
  • [x] All sentences begin with a capital letter.
  • [x] All sentences are terminated by a period.
  • [x] I am able to understand all the help messages, if not, exchange with the PO or TW to rewrite them.
• [ ] After having created the PR, I will make sure that all the tests provided in this PR have run and passed.