Add comprehensive unit tests for TLS profile parsing, validation, and application.

Test files to create/modify:

• apis/config/v1beta2/validation_test.go - Test TLS validation
• cmd/kueue/main_test.go or pkg/util/tls/tls_test.go - Test TLS config conversion

Test cases:

• Valid TLS versions (1.0, 1.1, 1.2, 1.3) are accepted
• Invalid TLS versions are rejected
• Valid cipher suites are accepted
• Invalid cipher suite names are rejected
• Default values are applied when not specified
• TLS config is correctly converted to Go tls.Config

Acceptance Criteria:

• Unit tests cover all TLS profile types
• Tests verify validation logic
• Tests verify default value application
• Code coverage meets project requirements

Depends on: OCPKUEUE-452, OCPKUEUE-453, OCPKUEUE-454 (implementation stories)