build(deps): bump golang from 1.20.7 to 1.21.2 in /sidecar #1110

Job	Run time
Test Helm chart with cert-manager	8m 56s
Test Helm chart with cert-manager	8m 35s
Build tailing sidecar operator	2m 43s
Build tailing sidecar operator	2m 43s
markdownlint	37s
markdownlint	37s
Test Helm chart	8m 21s
Test Helm chart	8m 56s
Test Helm chart with custom configuration	8m 16s
Test Helm chart with custom configuration	8m 11s
Test resources created without Helm chart	9m 27s
Test resources created without Helm chart	9m 53s
yamllint	9s
yamllint	9s
	1h 17m 33s

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