message: allow to overwrite image, dockerfile, context per enviornment
diff: @@ -250,6 +250,13 @@ if [[ ( "$BUILD_TYPE" == "pullrequest" || "$BUILD_TYPE" == "branch" ) && ! $TH
  # allow to overwrite image that we pull
  OVERRIDE_IMAGE=$(cat $DOCKER_COMPOSE_YAML | shyaml get-value services.$IMAGE_NAME.labels.lagoon\\.image false)
  +
  + # allow to overwrite image that we pull for this environment and service
  + ENVIRONMENT_IMAGE_OVERRIDE=$(cat .lagoon.yml | shyaml get-value environments.${BRANCH//./\\.}.overwrites.$SERVICE_NAME.image false)
  + if [ ! $ENVIRONMENT_IMAGE_OVERRIDE == "false" ]; then
  + OVERRIDE_IMAGE=$ENVIRONMENT_IMAGE_OVERRIDE
  + fi
  +
  if [ ! $OVERRIDE_IMAGE == "false" ]; then
  # expand environment variables from ${OVERRIDE_IMAGE}
  PULL_IMAGE=$(echo "${OVERRIDE_IMAGE}" | envsubst)
  @@ -261,6 +268,12 @@ if [[ ( "$BUILD_TYPE" == "pullrequest" || "$BUILD_TYPE" == "branch" ) && ! $TH
  else
  # Dockerfile defined, load the context and build it
  + # allow to overwrite build dockerfile for this environment and service
  + ENVIRONMENT_DOCKERFILE_OVERRIDE=$(cat .lagoon.yml | shyaml get-value environments.${BRANCH//./\\.}.overwrites.$SERVICE_NAME.build.dockerfile false)
  + if [ ! $ENVIRONMENT_DOCKERFILE_OVERRIDE == "false" ]; then
  + DOCKERFILE=$ENVIRONMENT_DOCKERFILE_OVERRIDE
  + fi
  +
  # We need the Image Name uppercase sometimes, so we create that here
  IMAGE_NAME_UPPERCASE=$(echo "$IMAGE_NAME" | tr '[:lower:]' '[:upper:]')
  @@ -269,6 +282,13 @@ if [[ ( "$BUILD_TYPE" == "pullrequest" || "$BUILD_TYPE" == "branch" ) && ! $TH
  TEMPORARY_IMAGE_NAME="${NAMESPACE}-${IMAGE_NAME}"
  BUILD_CONTEXT=$(cat $DOCKER_COMPOSE_YAML | shyaml get-value services.$IMAGE_NAME.build.context .)
  +
  + # allow to overwrite build context for this environment and service
  + ENVIRONMENT_BUILD_CONTEXT_OVERRIDE=$(cat .lagoon.yml | shyaml get-value environments.${BRANCH//./\\.}.overwrites.$SERVICE_NAME.build.context false)
  + if [ ! $ENVIRONMENT_BUILD_CONTEXT_OVERRIDE == "false" ]; then
  + BUILD_CONTEXT=$ENVIRONMENT_BUILD_CONTEXT_OVERRIDE
  + fi
  +
  if [ ! -f $BUILD_CONTEXT/$DOCKERFILE ]; then
  echo "defined Dockerfile $DOCKERFILE for service $IMAGE_NAME not found"; exit 1;
  fi
  