[client] new Security-Platform IdentityType (#10452)

[CelineSebe]

Proposed changes

• add new constant 'SECURITY'
• add security_platform_type
  link to opencti PR

Related issues

• Create security platform entity (relation & import/export python included) opencti#10452

Checklist

• I consider the submitted work as finished
• I tested the code for its functionality
• I wrote test cases for the relevant uses case
• I added/update the relevant documentation (either on github or on notion)
• Where necessary I refactored code to improve the overall quality

Further comments

If this is a relatively large or complex change, kick off the discussion by explaining why you chose the solution you did and what alternatives you considered, etc...