dashboard, env/linux-x86-bookworm: remove known issue tag

This removes the known issue tag for the linux-amd64-bookworm builder.
It also removes the unused bootstrap version of Go from the container
image.

Fixes golang/go#60787

Change-Id: Ideafbdf400f45fd7dffc018a87a8b444c6cb1672
Reviewed-on: https://go-review.googlesource.com/c/build/+/506337
Run-TryBot: Carlos Amedee <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
Auto-Submit: Carlos Amedee <[email protected]>
TryBot-Result: Gopher Robot <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>

Author: cagedmantis

dashboard/builders.go

@@ -1886,7 +1886,6 @@ func init() {
 		env: []string{
 			"GO_DISABLE_OUTBOUND_NETWORK=1",
 		},
-		KnownIssues: []int{60787},
 	})
 	addBuilder(BuildConfig{
 		Name:     "linux-amd64-bullseye",

env/linux-x86-bookworm/Dockerfile

@@ -60,20 +60,6 @@ RUN apt-get update && apt-get install -y \
 	swig \
 	&& rm -rf /var/lib/apt/lists/*
 
-RUN mkdir -p /go1.4-amd64 \
-	&& ( \
-		curl --silent https://storage.googleapis.com/golang/go1.4.linux-amd64.tar.gz | tar -C /go1.4-amd64 -zxv \
-	) \
-	&& mv /go1.4-amd64/go /go1.4 \
-	&& rm -rf /go1.4-amd64 \
-	&& rm -rf /go1.4/pkg/linux_amd64_race \
-		/go1.4/api \
-		/go1.4/blog \
-		/go1.4/doc \
-		/go1.4/misc \
-		/go1.4/test \
-	&& find /go1.4 -type d -name testdata | xargs rm -rf
-
 COPY --from=stage0 /go/bin/stage0 /usr/local/bin/stage0
 
 CMD ["/usr/local/bin/stage0"]