minor symfony#9062 Recommend being lenient only with other vendors (greg0ire)

This PR was merged into the 4.0 branch.

Discussion
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Recommend being lenient only with other vendors

If a bundle introduces a deprecation, it should not use the deprecated
 path itself anymore.

Commits
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64a9aa5 Recommend being lenient only with other vendors

Author: javiereguiluz

bundles/best_practices.rst

@@ -197,9 +197,9 @@ of Symfony and the latest beta release:
         include:
               # Minimum supported dependencies with the latest and oldest PHP version
             - php: 7.2
-              env: COMPOSER_FLAGS="--prefer-stable --prefer-lowest" SYMFONY_DEPRECATIONS_HELPER="weak"
+              env: COMPOSER_FLAGS="--prefer-stable --prefer-lowest" SYMFONY_DEPRECATIONS_HELPER="weak_vendors"
             - php: 7.0
-              env: COMPOSER_FLAGS="--prefer-stable --prefer-lowest" SYMFONY_DEPRECATIONS_HELPER="weak"
+              env: COMPOSER_FLAGS="--prefer-stable --prefer-lowest" SYMFONY_DEPRECATIONS_HELPER="weak_vendors"
 
               # Test the latest stable release
             - php: 7.0