Add constrain to check if plugin can be published.

[rohitpavaskar]

Q	A
Bug fix? (use the a.b branch)	[N ]
New feature/enhancement? (use the a.x branch)	[Y]
Deprecations?	[N]
BC breaks? (use the c.x branch)	[N]
Automated tests included?	[Y]
Related user documentation PR URL	mautic/mautic-documentation#...
Related developer documentation PR URL	mautic/developer-documentation#...
Issue(s) addressed	Fixes #...

Description:

When authorizing the plugin, if my user doesn't have particular access, I should receive an error and fail to authorize the plugin. This i new constrain which we need to add in any plugin which will not allow user to publish the plugin if user don't have sufficient access.
Also clear the access and refresh token whenever credentials are changed.

Example usage in a plugin:

class CanPublishValidatorSubscriber implements EventSubscriberInterface
{
    public static function getSubscribedEvents()
    {
        return [
            PluginEvents::PLUGIN_IS_PUBLISHED_STATE_CHANGING => ['onPublishStateChange', 0],
        ];
    }

    public function onPublishStateChange(PluginIsPublishedEvent $event)
    {
        if ('YourIntegrationName' !== $event->getIntegrationName() || 1 !== $event->getValue()) {
            return;
        }

        // custom logic here...

        $event->setCanPublish($enabled);
        $event->setMessage($message);
    }
}

Steps to test this PR:

1. Open this PR on Gitpod or pull down for testing locally (see docs on testing PRs here)
2. Not testable without adding constrain in plugin.

[codecov]

Codecov Report

Attention: Patch coverage is 85.93750% with 9 lines in your changes are missing coverage. Please review.

Project coverage is 61.64%. Comparing base (4883fa0) to head (74fabfc).

Additional details and impacted files

@@             Coverage Diff              @@
##                5.x   #13696      +/-   ##
============================================
+ Coverage     61.62%   61.64%   +0.01%     
- Complexity    34145    34169      +24     
============================================
  Files          2245     2249       +4     
  Lines        102077   102134      +57     
============================================
+ Hits          62909    62963      +54     
- Misses        39168    39171       +3     

Files	Coverage Δ
...dles/PluginBundle/Event/PluginIsPublishedEvent.php	100.00% <100.00%> (ø)
...ndles/PluginBundle/Exception/ApiErrorException.php	41.17% <100.00%> (+24.50%)	⬆️
...undles/PluginBundle/Form/Constraint/CanPublish.php	100.00% <100.00%> (ø)
...uginBundle/Form/Constraint/CanPublishValidator.php	100.00% <100.00%> (ø)
app/bundles/PluginBundle/Form/Type/DetailsType.php	93.33% <100.00%> (+0.11%)	⬆️
...les/PluginBundle/Form/Type/FeatureSettingsType.php	74.07% <100.00%> (ø)
app/bundles/PluginBundle/MauticPluginBundle.php	100.00% <100.00%> (ø)
...ndles/PluginBundle/Controller/PluginController.php	46.31% <83.33%> (+3.21%)	⬆️
...s/PluginBundle/Integration/AbstractIntegration.php	34.00% <33.33%> (+0.33%)	⬆️

... and 1 file with indirect coverage changes

[escopecz]

Thanks Rohit! I found a few places that could improve. Please go through the suggestions and apply them if they make sense.

[escopecz]

Thank you, Rohit! I see no problems in the code changes 👍

[escopecz]

Since this cannot be directly tested without a proprietary plugin, can someone do a second code review? Perhaps @kuzmany ?