minor #25898 [minor] SCA: reduce repetitive method calls (sequential and in loop) (kalessil)

This PR was merged into the 2.7 branch.

Discussion
----------

[minor] SCA: reduce repetitive method calls (sequential and in loop)

| Q             | A
| ------------- | ---
| Branch?       | 2.7
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | n/a
| License       | MIT
| Doc PR        | n/a

Commits
-------

609372252f SCA: get rid of repetitive calls

Author: fabpot

ExecutionContext.php

@@ -197,8 +197,9 @@ public function validate($value, $subPath = '', $groups = null, $traverse = fals
     {
         $propertyPath = $this->getPropertyPath($subPath);
 
+        $visitor = $this->globalContext->getVisitor();
         foreach ($this->resolveGroups($groups) as $group) {
-            $this->globalContext->getVisitor()->validate($value, $group, $propertyPath, $traverse, $deep);
+            $visitor->validate($value, $group, $propertyPath, $traverse, $deep);
         }
     }