bug #746 Allow released versions of the deprecation contract (stof)

This PR was merged into the 1.0-dev branch.

Discussion
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Allow released versions of the deprecation contract

This ensures that the package can be installed with `stable` as minimum stability.

Commits
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81e72a1 Allow released versions of the deprecation contract

composer.json

@@ -19,7 +19,7 @@
         "symfony/config": "^3.4|^4.0|^5.0",
         "symfony/console": "^3.4|^4.0|^5.0",
         "symfony/dependency-injection": "^3.4|^4.0|^5.0",
-        "symfony/deprecation-contracts": "^2.3",
+        "symfony/deprecation-contracts": "^2.2",
         "symfony/filesystem": "^3.4|^4.0|^5.0",
         "symfony/finder": "^3.4|^4.0|^5.0",
         "symfony/framework-bundle": "^3.4|^4.0|^5.0",