minor #10353 There is no public folder in 3.4 (ersin-demirtas)

This PR was merged into the 3.4 branch.

Discussion
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There is no public folder in 3.4

There is no public/ folder in 3.4 instead there is web/ folder.

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Commits
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df1dff6 There is no public folder in 3.4

Author: javiereguiluz

frontend/encore/installation-no-flex.rst

@@ -39,7 +39,7 @@ Next, create a new ``webpack.config.js`` file at the root of your project:
 
     Encore
         // directory where compiled assets will be stored
-        .setOutputPath('public/build/')
+        .setOutputPath('web/build/')
         // public path used by the web server to access the output path
         .setPublicPath('/build')
         // only needed for CDN's or sub-directory deploy