fix(deps): bump alpine from 3.20.3 to 3.21.0 (#106)

Bumps alpine from 3.20.3 to 3.21.0.


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Dockerfile

@@ -1,4 +1,4 @@
-FROM alpine:3.20.3 AS setup-base
+FROM alpine:3.21.0 AS setup-base
 RUN apk --no-cache add curl~=8
 
 # renovate: datasource=github-releases depName=gruntwork-io/terragrunt