[9.0] Removal of Arcsight Module and Modules Framework

[robbavey]

For 9.0, we will be removing the Arcsight module, and as a result, we can remove the Modules Framework as a whole

On the main branch only:

• Remove the Arcsight module from x-pack #16740
• Remove any link to modules from the documentation on the main branch of Logstash. #16739
• Remove the Modules framework code from the main branch of Logstash. #16741
  • Remove any references to modules in Logstash configuration files (logstash.yml), and command-line runner
  • Remove any reference to modules in translation files
  • Remove/change any tests that refer to modules