minor #114 Remove Symfony deprecation contracts from required packages (cezarystepkowski)

This PR was merged into the 0.2-dev branch.

Discussion
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Remove Symfony deprecation contracts from required packages

`symfony/deprecation-contracts`  is not needed any more, because the legacy code that triggered deprecations has been removed.

Additionally, it caused problems when trying to install `qossmic/rich-model-forms-bundle` on projects that require `symfony/deprecation-contracts` in version 3.

Commits
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d67ab92 Remove Symfony deprecation contracts from required packages

Author: xabbuh

composer.json

@@ -22,7 +22,6 @@
         "symfony/form": "^4.4||^5.3||^6.0",
         "symfony/framework-bundle": "^4.4||^5.3||^6.0",
         "symfony/http-kernel": "^4.4||^5.3||^6.0",
-        "symfony/deprecation-contracts": "^2.1",
         "symfony/options-resolver": "^4.4||^5.3||^6.0",
         "symfony/property-access": "^4.4||^5.3||^6.0"
     },