Update mega-linter.yml to disable JSON_PRETTIER linter + Readme fix

[riosengineer]

No description provided.

[github-actions]

🦙 MegaLinter status: ⚠️ WARNING

Descriptor	Linter	Files	Fixed	Errors	Warnings	Elapsed time
⚠️ MARKDOWN	markdownlint	1		1	0	0.46s
✅ MARKDOWN	markdown-link-check	1		0	0	1.66s
✅ MARKDOWN	markdown-table-formatter	1		0	0	0.21s
✅ REPOSITORY	devskim	yes		no	no	1.32s
✅ REPOSITORY	dustilock	yes		no	no	0.01s
✅ REPOSITORY	git_diff	yes		no	no	0.01s
✅ REPOSITORY	secretlint	yes		no	no	1.02s
✅ REPOSITORY	syft	yes		no	no	1.31s
✅ REPOSITORY	trivy-sbom	yes		no	no	0.44s
✅ REPOSITORY	trufflehog	yes		no	no	2.93s

See detailed report in MegaLinter reports
Set VALIDATE_ALL_CODEBASE: true in mega-linter.yml to validate all sources, not only the diff