IndexError when Grype "Identifiers" are blank

[ForkedProject10]

Describe the bug
An IndexError is thrown when an SBOM is processed that contains an empty Identifiers set.

Steps to reproduce

Use SecScanner2JUnit utility to process SBOM from a scan that produced an empty set of Identifiers. For example:

        {
            "language": "",
            "category": "container_scanning",
            "message": "BIT-redis-2025-27151 in redis-7.4.3-0",
            "description": "Redis is an open source, in-memory database that persists on disk. In versions starting from 7.0.0 to before 8.0.2, a stack-based buffer overflow exists in redis-check-aof due to the use of memcpy with strlen(filepath) when copying a user-supplied file path into a fixed-size stack buffer. This allows an attacker to overflow the stack and potentially achieve code execution. This issue has been patched in version 8.0.2.",
            "cve": "BIT-redis-2025-27151",
            "severity": "Medium",
            "confidence": "Unknown",
            "remediateMetadata": {
                "package_name": "redis",
                "package_version": "7.4.3-0",
                "fixed_version": "8.0.2",
                "summary": "Upgrade redis to 8.0.2"
            },
            "solution": "Upgrade redis to 8.0.2",
            "scanner": {
                "id": "grype",
                "name": "grype"
            },
            "location": {
                "dependency": {
                    "package": {
                        "name": "redis"
                    },
                    "version": "7.4.3-0"
                },
                "operating_system": "",
                "image": ""
            },
            "identifiers": [],
            "links": [
                {
                    "url": "https://github.com/redis/redis/releases/tag/8.0.2"
                },
                {
                    "url": "https://github.com/redis/redis/security/advisories/GHSA-5453-q98w-cmvm"
                },
                {
                    "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-27151"
                }
            ]
        }

This throws an IndexError exception that reports the following:

Traceback (most recent call last):
  File "/usr/local/bin/ss2ju", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/usr/local/lib/python3.12/site-packages/secscanner2junit/__init__.py", line 74, in main
    testsuite = parser.parse()
                ^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/secscanner2junit/container_scanning.py", line 37, in parse
    testcases.append(self.parse_vulnerability(raw_vulnerability))
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/secscanner2junit/container_scanning.py", line 19, in parse_vulnerability
    tc = TestCase(name=vulnerability.get_testcase_name(),
                       ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/local/lib/python3.12/site-packages/secscanner2junit/vulnerability.py", line 78, in get_testcase_name
    return self.__identifiers[0].get_name() + id_part + severity_part
           ~~~~~~~~~~~~~~~~~~^^^
IndexError: list index out of range

Expected behavior
ss2ju properly handles null identifiers.