chore(deps): update alpine docker tag to v3.20

Author: plural-renovate[bot]

Dockerfile

@@ -19,7 +19,7 @@ COPY /internal internal/
 # Build
 RUN CGO_ENABLED=0 GOOS=linux GOARCH=${TARGETARCH} GO111MODULE=on go build -a -o deployment-agent cmd/agent/**
 
-FROM alpine:3.18
+FROM alpine:3.20
 WORKDIR /workspace
 
 COPY --from=builder /workspace/deployment-agent .