Add comment explainig the load-bearing debug flags (#9443)

tools/docker/deploy.sh

@@ -46,6 +46,10 @@ ParseRequestedArch "${2}"
 TagAndPushForAllRequestedArch() {
     DOCKER_REPO="${DOCKER_HUB_ORG}/${1}"
     for TARGET_ARCH in "${ALL_REQUESTED_ARCH[@]}"; do
+        # NOTE: In early 2022, we were experiencing regular "docker push"
+        # timeouts, so we added these "--debug" flags to learn more. Since we
+        # added them, we haven't had another timeout, so until we experience
+        # another timeout & can get the deubg logs, we're leaving them in.
         docker --debug push "${DOCKER_REPO}:${TARGET_ARCH}-${TAG_BASE}"
 
         if [[ "${TAG_BASE}" =~ ^v[0-9]+\.[0-9]+\.[0-9]+$ ]]; then