Update golang Docker tag to v1.20

renovate[bot] · web-flow · commit 149e4198fa0e · 2023-03-18T16:08:51.000Z
diff --git a/Dockerfile b/Dockerfile
@@ -2,7 +2,7 @@
 ###############################
 # Build the doctree Go binary #
 ###############################
-FROM golang:1.18-alpine as builder
+FROM golang:1.20-alpine@sha256:1db127655b32aa559e32ed3754ed2ea735204d967a433e4b605aed1dd44c5084 as builder
 
 RUN apk add --no-cache git build-base
 COPY . /doctree
