[CodeQuality] Fix StrlenZeroToIdenticalEmptyStringRector skipping non-matching binary

docs/AllRectorsOverview.md

@@ -3547,7 +3547,7 @@ services:
 
 - class: `Rector\Php\Rector\FuncCall\PregReplaceEModifierRector`
 
-The /e modifier is no longer supported, use preg_replace_callback instead 
+The /e modifier is no longer supported, use preg_replace_callback instead
 
 ```diff
  class SomeClass

docs/NodesOverview.md

@@ -917,7 +917,7 @@ if (true) {
 
 ```php
 ?>
-<strong>feel</strong><?php 
+<strong>feel</strong><?php
 ```
 <br>
 

packages/CodeQuality/src/Rector/FuncCall/StrlenZeroToIdenticalEmptyStringRector.php

@@ -64,9 +64,7 @@ CODE_SAMPLE
             }
 
             $variable = $node->left->args[0]->value;
-        }
-
-        if ($node->right instanceof FuncCall) {
+        } elseif ($node->right instanceof FuncCall) {
             if (! $this->isName($node->right, 'strlen')) {
                 return null;
             }
@@ -76,6 +74,8 @@ CODE_SAMPLE
             }
 
             $variable = $node->right->args[0]->value;
+        } else {
+            return null;
         }
 
         /** @var Expr $variable */