[DOCS]: Add an Example of Validating SBOMs

Create documentation to guide users on validating SBOMs.

The CycloneDX Python library can validate an SBOM based on the schema, independent of the library's support for SBOM serialization, which is a valuable feature. However, the current documentation lacks clear examples and instructions on effectively utilizing this validation functionality.

The following points should be addressed in the documentation:

An overview of how to validate SBOMs based on schema specifications.
Examples demonstrating the validation process, including code snippets using JsonStrictValidator and other relevant classes.