chore(deps): Bump golang from 1.21.2-alpine3.18 to 1.21.3-alpine3.18 …

…in /docker (#2658)

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Bumps golang from 1.21.2-alpine3.18 to 1.21.3-alpine3.18.


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docker/Dockerfile_txsim

@@ -1,5 +1,5 @@
 # Stage 1: generate celestia-appd binary
-FROM --platform=$BUILDPLATFORM docker.io/golang:1.21.2-alpine3.18 as builder
+FROM --platform=$BUILDPLATFORM docker.io/golang:1.21.3-alpine3.18 as builder
 # hadolint ignore=DL3018
 RUN apk update && apk add --no-cache \
     gcc \