tools: compare ICU checksums before file changes

Otherwise we end up with an bad update PR when checksums don't match.

Refs: #50495
PR-URL: #50522
Reviewed-By: Marco Ippolito <marcoippolito54@gmail.com>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>

tools/dep_updaters/update-icu.sh

@@ -42,23 +42,23 @@ NEW_VERSION_TGZ_URL="https://github.com/unicode-org/icu/releases/download/releas
 
 NEW_VERSION_MD5="https://github.com/unicode-org/icu/releases/download/release-${DASHED_NEW_VERSION}/icu4c-${LOW_DASHED_NEW_VERSION}-src.md5"
 
-./configure --with-intl=full-icu --with-icu-source="$NEW_VERSION_TGZ_URL"
-
-"$TOOLS_DIR/icu/shrink-icu-src.py"
-
-rm -rf "$DEPS_DIR/icu"
-
 CHECKSUM=$(curl -sL "$NEW_VERSION_MD5" | grep "$NEW_VERSION_TGZ" | grep -v "\.asc$" | awk '{print $1}')
 
 GENERATED_CHECKSUM=$( curl -sL "$NEW_VERSION_TGZ_URL" | md5sum | cut -d ' ' -f1)
 
-echo "Comparing checksums: deposited $CHECKSUM with $GENERATED_CHECKSUM"
+echo "Comparing checksums: deposited '$CHECKSUM' with '$GENERATED_CHECKSUM'"
 
 if [ "$CHECKSUM" != "$GENERATED_CHECKSUM" ]; then
   echo "Skipped because checksums do not match."
   exit 0
 fi
 
+./configure --with-intl=full-icu --with-icu-source="$NEW_VERSION_TGZ_URL"
+
+"$TOOLS_DIR/icu/shrink-icu-src.py"
+
+rm -rf "$DEPS_DIR/icu"
+
 perl -i -pe "s|\"url\": .*|\"url\": \"$NEW_VERSION_TGZ_URL\",|" "$TOOLS_DIR/icu/current_ver.dep"
 
 perl -i -pe "s|\"md5\": .*|\"md5\": \"$CHECKSUM\"|" "$TOOLS_DIR/icu/current_ver.dep"