clarify the php version supported for FusionDirectory 1.3.x

hello,

we need to update our documentation as due to the recnt work FusionDirectory 1.3.1 will be only working on php 7.3

Cheers

cloned from user-manual#193 (closed)

changed milestone to %FusionDirectory 1.3.1

added Changed PJ2003-0342 labels

assigned to @bmortier

removed Changed label

removed PJ2003-0342 label

reopened

added PJ2003-0343 label

created branch 66-clarify-the-php-version-supported-for-fusiondirectory-1-3-x to address this issue

mentioned in commit f862f1c2

added Fixed label