[Backport release_3_6] [Bugfix] Load relations from embedded layers

[3liz-bot]

Backport #3899
Authored by: @mind84

[Gustry]

it seems the original PR was valid only for 3.7 ?
On 3.6, both phpunit and playwright are failing (not a false positive)

[rldhont]

I have backported 2 lines of code from this commit 81f600d

I have added

                    'relationName' => (string) $relationObj->name,
                    'relationId' => (string) $relationObj->id,

to https://github.com/3liz/lizmap-web-client/blob/release_3_6/lizmap/modules/lizmap/lib/Project/QgisProject.php#L1481

[mind84]

it seems the original PR was valid only for 3.7 ? On 3.6, both phpunit and playwright are failing (not a false positive)

Hi @Gustry,

sorry, yes, I've not considered the backport to previous versions, I'll work on it.

[Gustry]

As talked by email, the branch can't be updated by @mind84 because it's hosted on 3Liz repo. A new one will be opened.