Allow Symfony 7 + require PHP 8.1

Otherwise no changes.

First stable release

Amended the documentation and the expectation is that both this bundle and the underlying library should be fairly stable by now.

Support new filter

Support new RemoveNonAlphabetic filter

Bump underlying dependencies

For both string and debug dependencies.

Allow Symfony 6

Also fix the documentation a bit by removing mentions of annotations.

Set minimum PHP version to PHP8

• Adapt to new Attribute directory instead of the previous Annotation directory from underlying strings library (BC break)
• Cover tests with Psalm

v0.9.2

Add StreamlineEmail filter as a service

Add PHP8 attributes to documentation

Also changed the following:

• Update dependencies
• Test bundle in PHP8
• Adjust configuration

Better support typed properties

Upgrades the underlying squirrelphp/strings component. This
removes compatibility to diverging property paths defined
in the form, we now only support direct properties which are
mapped 1:1 in the form.

Note that if filter annotations are used without direct mappings,
this might lead to errors and/or not work anymore.

The PHP 8 support is preliminary, as it was not tested yet.

v0.8.6

Relax PHP version constraint