CSPL-4153: Update dependencies to fix security vulnerabilities

[gabrielm-splunk]

Summary

Updates dependencies to address security vulnerabilities identified in VULN tickets.

Changes

• google.golang.org/grpc: v1.78.0 → v1.79.3 (Fixes VULN-67797 - CVE-2026-33186)
• github.com/buger/jsonparser: v1.1.1 → v1.1.2 (Fixes VULN-67794)
• Go stdlib: 1.25.7 → 1.25.8 (Fixes VULN-65734)
• gnutls: Updated via explicit microdnf update in Dockerfile (Fixes VULN-69140)
• Other dependencies updated to latest compatible versions via go get -u

Testing

• Unit tests passing (running)
• GitLab smoke tests pending
• GitLab integration tests pending
• Container scan pending

Next Steps

• Wait for unit tests to complete
• Trigger GitLab CI/CD with container scan enabled
• Verify all VULN tickets are resolved in container scan results

Related Issues

• Fixes: CSPL-4153
• Resolves: VULN-67797, VULN-67794, VULN-65734, VULN-69140

🤖 Generated with Claude Code

[gabrielm-splunk]

✅ Unit Tests Passed

All unit tests completed successfully:

• Test Suite: PASSED
• Coverage: 97.3% of statements
• Composite Coverage: 83.5% of statements

🔍 Container Scan Pipeline Triggered

• Pipeline: https://cd.splunkdev.com/splunk-operator/splunk-operator-cicd/-/pipelines/35437356
• Will verify VULN tickets are resolved in the downstream conscan pipeline

[gabrielm-splunk]

✅ Go Version Updated in All Locations

Updated additional Go version references as requested:

Files Updated:

• ✅ : GO_VERSION=1.25.8
• ✅ Dockerfile.distroless: FROM golang:1.25.8

Verification:

• All three Dockerfiles now use Go 1.25.8
• GitHub workflows reference GO_VERSION from .env (automatically updated)
• Comprehensive search confirms no remaining 1.25.7 references (except historical changelog)

Changes pushed in: 269658b

Ready for re-review! 🚀

[gabrielm-splunk]

🔄 Commits Updated

Force-pushed to clean up commit history with proper author name and DCO signoff for GitLab compatibility.

All changes remain the same:

• ✅ Go 1.25.8 in all locations (go.mod, Dockerfile, Dockerfile.distroless, .env)
• ✅ grpc v1.79.3
• ✅ jsonparser v1.1.2
• ✅ gnutls update

Ready for re-review!