docs: Add all finalized tech lead forum standards

docs/libraries-tools/gcp-terraform/index.md

docs/reference/tech-lead-forum.md

docs/standards-and-compliance/change-management.md

docs/standards-and-compliance/devsecops-cd.md

docs/standards-and-compliance/devsecops-cicd.md

docs/standards-and-compliance/devsecops-dev.md

docs/standards-and-compliance/images/changemanagement-1.png

docs/standards-and-compliance/images/changemanagement-2.png

docs/standards-and-compliance/images/changemanagement-3.png

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docs/standards-and-compliance/images/changemanagement-5.png

docs/standards-and-compliance/images/changemanagement-6.png

docs/standards-and-compliance/images/changemanagement-7.png

docs/standards-and-compliance/images/devsecops-cd-1.png

docs/standards-and-compliance/images/devsecops-cicd-1.png

docs/standards-and-compliance/images/devsecops-cicd-2.png

docs/standards-and-compliance/images/devsecops-cicd-3.png

docs/standards-and-compliance/images/devsecops-cicd-4.png

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docs/standards-and-compliance/images/devsecops-cicd-6.png