Fixes #61. Add return type to methods

[tip2tail]

Fixes #61.

I created this PR to add Symfony 5.4 compatibility. There was a change to the Symfony\Bundle\SecurityBundle\DependencyInjection\Security\Factory\FormLoginFactory class in Symfony 5.4 that means we must provide the return types as part of the method signatures in LdapFormLoginFactory.

[tip2tail]

Paging @ChadSikorra - is this something you can check ad release please? Without this change, the bundle cannot be used in Symfony 5.4.

[tip2tail]

CC: @SebDev94 - might want to update your branch as well :)

[ramieita]

@tip2tail any Update ?

[tip2tail]

@ramieita Not sure what you are asking me on this one? I have not heard anything about this being merged yet.

You could use my branch instead which is what I am doing in my project

[ramieita]

@tip2tail i meant if this issue has been fixed or not , but obviously not :)

[HelloSebastian]

@tip2tail I have taken the fork from SebDev94. Thanks for the information! As soon as I use ldaptools in Symfony 5.4 I will update my branch.

Did you also have problems with the Doctrine cache? When I upgraded to Symfony 5.3, I had to downgrade the doctrine/cache to 1.12.1. Doctrine apparently deleted the cache in higher versions.