CI: Go mod tidy check

Dockerfile

@@ -26,6 +26,15 @@ RUN wget -O- -nv https://raw.githubusercontent.com/golangci/golangci-lint/master
 COPY .golangci.yml ./
 RUN golangci-lint run --timeout=10m
 
+FROM --platform=$BUILDPLATFORM base AS tidy
+RUN git init && \
+    git config user.email ci@localhost && \
+    git config user.name ci && \
+    git add -A && git commit -m ci && \
+    sed -i '/\/\/ indirect/d' go.mod && \
+    go mod tidy && \
+    git diff --exit-code -- go.mod
+
 FROM --platform=$BUILDPLATFORM base AS build
 COPY --from=qmcgaw/xcputranslate:v0.4.0 /xcputranslate /usr/local/bin/xcputranslate
 ARG TARGETPLATFORM