minor #21599 Remove -dev version from setup.rst in symfony 8 (carferdas)

This PR was merged into the 8.0 branch.

Discussion
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 Remove -dev version from setup.rst in symfony 8

Since version 8.0.0 has already been released, the -dev suffix can be removed from the version in the installation instructions.

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Commits
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062058f Remove -dev version from setup.rst in symfony 8

Author: javiereguiluz

setup.rst

@@ -48,10 +48,10 @@ application:
 .. code-block:: terminal
 
     # run this if you are building a traditional web application
-    $ symfony new my_project_directory --version="8.0.x-dev" --webapp
+    $ symfony new my_project_directory --version="8.0.x" --webapp
 
     # run this if you are building a microservice, console application or API
-    $ symfony new my_project_directory --version="8.0.x-dev"
+    $ symfony new my_project_directory --version="8.0.x"
 
 The only difference between these two commands is the number of packages
 installed by default. The ``--webapp`` option installs extra packages to give
@@ -63,12 +63,12 @@ Symfony application using Composer:
 .. code-block:: terminal
 
     # run this if you are building a traditional web application
-    $ composer create-project symfony/skeleton:"8.0.x-dev" my_project_directory
+    $ composer create-project symfony/skeleton:"8.0.x" my_project_directory
     $ cd my_project_directory
     $ composer require webapp
 
     # run this if you are building a microservice, console application or API
-    $ composer create-project symfony/skeleton:"8.0.x-dev" my_project_directory
+    $ composer create-project symfony/skeleton:"8.0.x" my_project_directory
 
 No matter which command you run to create the Symfony application. All of them
 will create a new ``my_project_directory/`` directory, download some dependencies