build(deps): bump golang from 1.20-alpine to 1.21-alpine in /docker (c…

…osmos#1138)

Bumps golang from 1.20-alpine to 1.21-alpine.


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docker/mockserv.Dockerfile

@@ -1,4 +1,4 @@
-FROM --platform=$BUILDPLATFORM golang:1.20-alpine AS build-env
+FROM --platform=$BUILDPLATFORM golang:1.21-alpine AS build-env
 
 # Set working directory for the build
 WORKDIR /src