Update docker.io/library/golang Docker tag to v1.22

This MR contains the following updates:

Package	Type	Update	Change
docker.io/library/golang	final	minor	1.21 -> 1.22

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Dockerfile

-FROM docker.io/library/golang:1.21 AS build
+FROM docker.io/library/golang:1.22 AS build
 ADD . /go/src
 WORKDIR /go/src
 RUN go build -tags netgo -o /webdav-server . && strip /webdav-server