Update golang:latest Docker digest to 2b1cbf2 (#65)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Dockerfile

@@ -1,6 +1,6 @@
 
 # Build a go app into a minimal docker image with timezone support and SSL cert chains.
-FROM golang:latest@sha256:4546829ecda4404596cf5c9d8936488283910a3564ffc8fe4f32b33ddaeff239 as builder
+FROM golang:latest@sha256:2b1cbf278ce05a2a310a3d695ebb176420117a8cfcfcc4e5e68a1bef5f6354da as builder
 ARG TARGETOS
 ARG TARGETARCH
 ARG BUILD_FLAGS=""