Support LTS Symfony (7.4) version

[Amunak]

The symfony/yaml requirement is really strict; 7.4 should be identical, just without deprecated stuff being dropped. For people who already run Symfony this is an issue since you probably want to be on an LTS release, and your package would force an upgrade to an unstable version.

[milinsky]

@Amunak Thank you for feedback! You're right, linking to the symfony/yaml package version is unnecessarily rigid. However, I must tell you that it is difficult for me to rely on any version. I tried to make the package as independent as possible. Moreover, it is difficult to rely on the symfony/yaml version, if only because Symfony itself does not use PSR, and this makes it very difficult to choose a version. I am ready to discuss and make changes. I haven't used Symfony for several years now, and your help would be very helpful in making the package useful to everyone.

[Amunak]

It should honestly be as simple as allowing the older LTS version. Symfony only removes BC breaks between the x.4 and x+1 version, so it should be perfectly backwards compatible.

Symfony does use semantic versioning (if that's what you meant); choosing the last LTS version and allowing the future ones is a good choice. If you want to keep it tight you could do ^7.4 || ^8.0, but realistically it's an old and stable package - you could also just allow them all or widen it to even old LTS versions: look at its changelog - unless you use any of the stuff added in recent releases (which you likely don't) you cold widen it even from 6.4 or such.

Or keep it at * and have it be the users' decision on what version to use. Again, most likely will work just fine for everyone.