fix: upgrade Renovate go version to 1.20

mentioned in commit 2297eb06

mentioned in merge request pmv!256 (merged)

mentioned in merge request gitlab-com/runbooks!5641 (merged)

mentioned in merge request bigquery-loader!99 (merged)

mentioned in merge request common-ci-tasks-images!97 (merged)

mentioned in merge request jsonnet-tool!54 (merged)

mentioned in merge request terra-transformer!242 (merged)

mentioned in merge request gitlab-org/release-tools!2280 (merged)

mentioned in merge request asdf-gl-infra!31 (merged)

mentioned in merge request fluentd-docker!38 (merged)

mentioned in merge request es-diagnostics!15

mentioned in merge request gitlab-com/gl-infra/k8s-workloads/common!268 (merged)

mentioned in merge request slackline!154 (merged)

mentioned in merge request gitlab-com/gl-infra/gitlab-dedicated/library/byok-status-exporter!18 (merged)

mentioned in merge request cmbr!165 (merged)

mentioned in merge request asdf-promtool!39 (merged)

mentioned in merge request gitlab-com/gl-infra/platform/runway/runwayctl!2 (merged)

mentioned in merge request gcp-quota-exporter!2 (merged)

mentioned in merge request es-diagnostics!18