[BUGFIX] Point new user to correct folder on first install

The FIRST_INSTALL needs to be created in the web root of your project
and not in the root of your project as that can be below the web root.

Releases: master
Resolves: #80671
Change-Id: Ib6ffc32e93b18d6792193761970fa9c1c866ba4f
Reviewed-on: https://review.typo3.org/52353


Tested-by: TYPO3com <no-reply@typo3.com>
Reviewed-by: Thomas Hohn <thomas@hohn.dk>
Reviewed-by: Mona Muzaffar <mona.muzaffar@gmx.de>
Tested-by: Mona Muzaffar <mona.muzaffar@gmx.de>
Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>

typo3/sysext/install/Resources/Private/Templates/Action/Common/FirstInstall.html

@@ -18,7 +18,7 @@
 				<div class="panel-body">
 					<p>
 						To proceed with the installation, create the file <strong>FIRST_INSTALL</strong>
-						in your root directory.
+						in your web root directory.
 						The filename is case-sensitive but the file itself can be empty.
 					</p>
 					<p>