Update golang Docker tag to v1.21.7 #270

Job	Run time
Flowzone / Event Types (pull_request, closed)	2s
Flowzone / Versioned source	32s
Flowzone / Clean GitHub release	0s
Flowzone / Is python	4s
Flowzone / Is rust	4s
Flowzone / Is docker	14s
Flowzone / Is npm	7s
Flowzone / Is balena	0s
Flowzone / Is custom	6s
Flowzone / Is CloudFormation	0s
Flowzone / Is website	0s
Flowzone / Is Terraform	0s
Flowzone / Finalize GitHub release	13s
Flowzone / Test CloudFormation	0s
Flowzone / Finalize CloudFormation	0s
Flowzone / Finalize balena	0s
Flowzone / Test Terraform	0s
Flowzone / Finalize Terraform	0s
Flowzone / Finalize rust	0s
Flowzone / Test rust	0s
Flowzone / Test python poetry	0s
Flowzone / Finalize python	0s
Flowzone / Test custom	0s
Flowzone / Finalize custom	0s
Flowzone / Clean custom	0s
Flowzone / Test npm	0s
Flowzone / Finalize npm	0s
Flowzone / Finalize npm docs	0s
Flowzone / Finalize docker	0s
Flowzone / Test docker	0s
Flowzone / Publish docker	0s
Flowzone / Publish npm	0s
Flowzone / Publish balena	0s
Flowzone / Publish rust	0s
Flowzone / Publish to test PyPI	0s
Flowzone / Publish website	0s
Flowzone / All tests	0s
Flowzone / Publish custom	0s
Flowzone / Publish Github release	0s
Flowzone / Always custom	0s
Flowzone / All jobs	0s
Flowzone / Auto-merge	0s
	1m 22s

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