use ldflags

Dockerfile

@@ -5,6 +5,7 @@ WORKDIR /telemetry-manager-workspace
 # Copy the Go Modules manifests
 COPY go.mod go.mod
 COPY go.sum go.sum
+COPY .git .git
 # cache deps before building and copying source so that we don't need to re-download as much
 # and so that source changes don't invalidate our downloaded layer
 RUN go mod download
@@ -16,8 +17,10 @@ COPY controllers/ controllers/
 COPY internal/ internal/
 COPY webhook/ webhook/
 
+RUN apk add git
+
 # Clean up unused (test) dependencies and build
-RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go mod tidy && go build -a -o manager main.go
+RUN CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go mod tidy && go build -ldflags="-X main.version=$(git rev-parse --short HEAD)" -a -o manager main.go
 
 FROM scratch