Lando tooling command syntax

I'm trying to set up a some tooling in my .lando.yml file to rapidly accomplish several tasks I do on every fresh WordPress install. Everything's working great except for if I try to use the [--extra-php] option in the wp-cli and syntax as demonstrated in the wp-cli docs.

I get the following error when I run the command: /bin/sh: 1: Syntax error: "(" unexpected

If I remove the code beginning at <<PHP and ending at the closing PHP, everything executes perfectly.

I assume I need to escape the parentheses in some way, but how to properly do that in YAML? Though I don't specifically get a YAML, so I'm not sure if that's actually the issue either.

Relevant section of config:
The error occurs at the first parenthesis.

tooling:
  npm:
    service: node
  wp-install:
    service: appserver
    cmd:
      - wp config create --dbname=wordpress --dbuser=wordpress --dbpass=wordpress --dbhost=database --extra-php <<'PHP' 
        define( 'WP_DEBUG', true ); 
        define( 'WP_DEBUG_LOG', true ); 
        define( 'ACF_PRO_LICENSE', 'XXX'); 
        PHP      
      - wp core install --url=http://$LANDO_APP.$LANDO_DOMAIN --title=XXX --admin_user=StudioAl --admin_password=XXX --admin_email=kerri@studioal.com
      - wp plugin install gravityformscli --activate
      - wp gf install --XXX --activate
      - wp plugin install "http://connect.advancedcustomfields.com/index.php?p=pro&a=download&k=XXX" --activate

Stock example of usage of the problem code in documentation for wp-cli, for reference

# Enable WP_DEBUG and WP_DEBUG_LOG
$ wp config create --dbname=testing --dbuser=wp --dbpass=securepswd --extra-php <<PHP
define( 'WP_DEBUG', true );
define( 'WP_DEBUG_LOG', true );
PHP
Success: Generated 'wp-config.php' file.

A YAML parser loads this:

  - wp config create --dbname=wordpress --dbuser=wordpress --dbpass=wordpress --dbhost=database --extra-php <<PHP 
    define( 'WP_DEBUG', true ); 
    define( 'WP_DEBUG_LOG', true ); 
    define( 'ACF_PRO_LICENSE', 'XXX'); 
    PHP

as a sequence with a single item that is a string which doesn't have any newlines. That is something like:

["wp config create --dbname=wordpress --dbuser=wordpress --dbpass=wordpress --dbhost=database --extra-php <<PHP define( 'WP_DEBUG', true ); define( 'WP_DEBUG_LOG', true ); define( 'ACF_PRO_LICENSE', 'XXX'); PHP"]

If that string is handed to a (Unix) shell, it will IMO not interpret that as an heredoc because the delimiting identifier (PHP) doesn't occur on a line of its own.

You might have more success if you make that scalar a literal style scalar by inserting a pipe symbol before the scalar:

  - |
    wp config create --dbname=wordpress --dbuser=wordpress --dbpass=wordpress --dbhost=database --extra-php <<PHP 
    define( 'WP_DEBUG', true ); 
    define( 'WP_DEBUG_LOG', true ); 
    define( 'ACF_PRO_LICENSE', 'XXX'); 
    PHP

that way the string is loaded include the newlines (but without leading spaces)