refactor(gh): Pull out formatter

This makes for easier local testing.

docker/Dockerfile

@@ -6,5 +6,6 @@ RUN wget https://github.com/crate-ci/typos/releases/download/v${VERSION}/typos-v
     tar -xzvf typos-v${VERSION}-x86_64-unknown-linux-musl.tar.gz && \
     mv typos /usr/local/bin
 COPY entrypoint.sh /entrypoint.sh
+COPY format_gh.sh /format_gh.sh
 WORKDIR /github/workspace
 ENTRYPOINT ["/bin/bash", "/entrypoint.sh"]

docker/entrypoint.sh

@@ -2,6 +2,8 @@
 
 set -eu
 
+SOURCE_DIR="$(dirname -- ${BASH_SOURCE[0]:-$0})";
+
 log() {
     echo -e "$1" >&2
 }
@@ -47,10 +49,5 @@ if [[ -n "${INPUT_CONFIG:-}" ]]; then
 fi
 
 log "$ ${CMD_NAME} ${ARGS}"
-${CMD_NAME} ${ARGS} --format json |
-  grep '"type":"typo"' |
-  jq --sort-keys --raw-output '"::warning file=\(.path),line=\(.line_num),col=\(.byte_offset)::\"\(.typo)\" should be \"" + (.corrections // [] | join("\" or \"") + "\".")' |
-  while IFS= read -r line; do
-    echo "$line"
-  done || true
+${CMD_NAME} ${ARGS} --format json | ${SOURCE_DIR}/format_gh.sh || true
 ${CMD_NAME} ${ARGS}

docker/format_gh.sh

@@ -0,0 +1,9 @@
+#!/bin/bash
+
+set -eu
+
+grep '"type":"typo"' |
+  jq --sort-keys --raw-output '"::warning file=\(.path),line=\(.line_num),col=\(.byte_offset)::\"\(.typo)\" should be \"" + (.corrections // [] | join("\" or \"") + "\".")' |
+  while IFS= read -r line; do
+    echo "$line"
+  done