Add support of Mercure running on a subdomain

[vrobert78]

On Pimcore PaaS, we'd like to switch from running Mercure in a side app to running Mercure as a Service.
But running Mercure as a Service implies that we run it on a subdomain.
Those modifications are required for the authentication layer.

There are also changes required in studio-ui-bundle, see pimcore/studio-ui-bundle#2095.

[vrobert78]

I replaced the cookieSameSite variable by jwt_cookie_strictness to have the same behavior as on Direct-Edit, see https://github.com/pimcore/direct-edit/pull/85/files.

[martineiber]

Thanks for your PR!
I just have a small suggestion to improve readability.

[sonarqubecloud]

Quality Gate passed

Issues
1 New issue
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube Cloud

[bluvulture]

@kingjia90 @martineiber can we merge this one?

[kingjia90]

@martineiber is that

studio-backend-bundle/src/DependencyInjection/Configuration.php

Line 52 in 363ae44

Cookie::SAMESITE_LAX,

is necessary? we need to adapt the direct-edit in case

[martineiber]

@martineiber is that

studio-backend-bundle/src/DependencyInjection/Configuration.php

Line 52 in 363ae44

Cookie::SAMESITE_LAX,

is necessary? we need to adapt the direct-edit in case

I do not see why it should be necessary. And can be removed.

From my point this looks good.

[martineiber]

LGTM

[martineiber]

@bluvulture @vrobert78 Can we merge this one from you side?

[bluvulture]

lgtm 👍