Update registry.hub.docker.com/library/golang Docker tag to v1.21.3

This MR contains the following updates:

Package	Type	Update	Change
registry.hub.docker.com/library/golang	stage	patch	1.21.2-alpine3.18 -> 1.21.3-alpine3.18

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Dockerfile

 # https://docs.docker.com/language/golang/build-images/#multi-stage-builds
 # https://hub.docker.com/_/golang/tags
-FROM  registry.hub.docker.com/library/golang:1.21.2-alpine3.18 AS build
+FROM  registry.hub.docker.com/library/golang:1.21.3-alpine3.18 AS build
 
 WORKDIR /app