minor #18821 [Doctrine][Testing] Mention how to run the commands that create the testing database (javiereguiluz)

This PR was merged into the 5.4 branch.

Discussion
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[Doctrine][Testing] Mention how to run the commands that create the testing database

Fixes #14586.

Commits
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06ac5a1 Mention how to run the commands that create the testing database

Author: javiereguiluz

testing.rst

@@ -398,6 +398,11 @@ After that, you can create the test database and all tables using:
     # create the tables/columns in the test database
     $ php bin/console --env=test doctrine:schema:create
 
+.. tip::
+
+    You can run these commands to create the database during the
+    :doc:`test bootstrap process <testing/bootstrap>`.
+
 .. tip::
 
     A common practice is to append the ``_test`` suffix to the original