[🐛] Wrong date is assigned to creation of SPDX result

[bsoroushian]

• node -v: v21.6.1
• npm -v: 10.2.4
• OS: (e.g. OSX, Linux, Windows, ...) MacOS
• Command run: snyk test --json | snyk2spdx --output=spdx.json

Expected behaviour

A valid date be attributed to the resulting SPDX report

Actual behaviour

An Invalid date with month 0 was assigned to the SPDX report

Steps to reproduce

Scan any arbitrary image and convert its result using snyk2spdx.

Debug log

{
  "id": "SPDXRef-docker-image|dev....",
  "specVersion": "SPDX-3.0",
  "creator": "Organization: Snyk Ltd",
  "created": "2024-00-02T20:01:35Z",
  "profile": [
    "base",
    "vulnerabilities"
  ],
  "description": "Snyk test result for project docker-image|dev.registry....-my-apps in SPDX SBOM format",

The function getDate() in generate-date.ts uses d.getMonth().toString() which is converting a zero-based number to string therefore in January date is zero. The day also would be wrong since d.getDay() will return a number between 0 and 6 (0 for Sunday and 6 for Saturday). Alternative would be to use date.toISOString().

Screenshots

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