Fix broken allowlist caused by update to schema v15

Why is this change being made?

Allowlist behavior was broken by removal of cve field in schema v15, implemented as part of Add support for Security Report Schema 15-0-0 t... (!2847 - merged).

• Re-enable alpine and oraclelinux EE integration tests now that the following have been completed:
  • Container scanning is missing coverage for Orac... (gitlab-org/gitlab#390868 - closed)
  • Import Alpine Linux vulnerabilities into Adviso... (gitlab-org/gitlab#361763 - closed)
• Fix incorrect allowlist integration tests
• Add integration tests for schema v15

Testing

• Container Scanning v5.3.1, with bug present

  • When CS_SCHEMA_MODEL: 14

    • ✅ Report artifact for schema version version: "14.1.2" shows no vulnerabilities, as expected.

  • When CS_SCHEMA_MODEL: 15

    • ❌ Report artifact for schema version version: "15.0.4" shows vulnerabilities, which is incorrect.

• Container Scanning v5.3.2, with bugfix

  • When CS_SCHEMA_MODEL: 14

    • ✅ Report artifact for schema version version: "14.1.2" shows no vulnerabilities, as expected.

  • When CS_SCHEMA_MODEL: 15

    • ✅ Report artifact for schema version version: "15.0.4" shows no vulnerabilities, as expected.

What are the relevant issue numbers?

Vulnerability allowlisting no longer works with... (gitlab-org/gitlab#398187 - closed)