Adds argument validations

[pschoffer]

Description

Apart from checking the input, I removed the defaults arguments on the function level, as those were never used and were only misleading (we always send all of the arguments).

Changelog Description

Plugin Updated: Search

Removes minor warning from wp vip-search health validate-contents when some parameters are not set. The correct default values are set both before and after this change.

Checklist

Please make sure the items below have been covered before requesting a review:

• This change works and has been tested locally (or has an appropriate fallback).
• This change works and has been tested on a Go sandbox.
• This change has relevant unit tests (if applicable).
• This change has relevant documentation additions / updates (if applicable).
• I've created a changelog description that aligns with the provided examples.

Steps to Test

1. Running lando wp vip-search health validate-contents Gives you:

Notice: Undefined index: last_post_id in /wp/wp-content/mu-plugins/search/includes/classes/commands/class-healthcommand.php on line 271 [$ /usr/local/bin/wp vip-search health validate-contents] [Automattic\VIP\Search\Commands\HealthCommand->validate_contents(), phar:///usr/local/binvendor/wp-cli/wp-cli/php/WP_CLI/Dispatcher/CommandFactory.php:98 call_user_func(), WP_CLI\Dispatcher\CommandFactory::WP_CLI\Dispatcher\{closure}(), phar:///usr/local/binvendor/wp-cli/wp-cli/php/WP_CLI/Dispatcher/Subcommand.php:451 call_user_func(), phar:///usr/local/binvendor/wp-cli/wp-cli/php/WP_CLI/Runner.php:371 WP_CLI\Dispatcher\Subcommand->invoke(), phar:///usr/local/binvendor/wp-cli/wp-cli/php/WP_CLI/Runner.php:394 WP_CLI\Runner->run_command(), phar:///usr/local/binvendor/wp-cli/wp-cli/php/WP_CLI/Runner.php:1160 WP_CLI\Runner->run_command_and_exit(), phar:///usr/local/binvendor/wp-cli/wp-cli/php/WP_CLI/Bootstrap/LaunchRunner.php:23 WP_CLI\Runner->start(), phar:///usr/local/binvendor/wp-cli/wp-cli/php/bootstrap.php:74 WP_CLI\Bootstrap\LaunchRunner->process(), phar:///usr/local/binvendor/wp-cli/wp-cli/php/wp-cli.php:27 WP_CLI\bootstrap(), phar:///usr/local/binphp/boot-phar.php:11 include('phar:///usr/local/binvendor/wp-cli/wp-cli/php/wp-cli.php'), /usr/local/bin/wp:4 include('phar:///usr/local/binphp/boot-phar.php')]

2. Apply the change - no more Notice.

[brandon-m-skinner]

r1395-stacks