Remove section in CGL about assignments in conditions (#705)

The recommendation to not use assignments in condition and add
extra parenthethese does not reflect current practice in core
and in newer examples in documentation.

Releases: master, 10.4, 9.5

Documentation/CodingGuidelines/CglPhp/PhpFileFormatting/PhpSyntaxFormatting.rst

@@ -208,26 +208,6 @@ Wrong usage of the ternary conditional operator::
 
    $result = ($useComma ? ',' : $useDot ? '.' : ';');
 
-Assignment in conditions should be avoided. However if it makes sense
-to do an assignment in a condition, it should be surrounded by the
-extra pair of brackets. Example::
-
-   if (($fields = $this->getFields())) {
-       // Do something
-   }
-
-The following is allowed, but not recommended::
-
-   if (false !== ($fields = $this->getFields())) {
-       // Do something
-   }
-
-The following is not allowed (missing the extra pair of brackets)::
-
-   while ($fields = $this->getFields()) {
-       // Do something
-   }
-
 
 Switch
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