Update Gitleaks to 3.3.0 in secrets analyzer of GitLab SAST

Update Gitleaks to 3.x in GitLab SAST secrets analyzer, while #12948 (closed) suggested to update it from 1.24 to 2.x.

Resources

• https://gitlab.com/gitlab-org/security-products/analyzers/secrets
• https://github.com/zricethezav/gitleaks/releases/tag/v3.3.0