bug #1179 Update setters (seb-jean)

This PR was merged into the main branch.

Discussion
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Update setters

Hi,

I updated setters because there is error :

`Expected argument of type "string", "null" given at property path "title".
`

Commits
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e1ba676 Update Post.php

Author: javiereguiluz

src/Entity/Post.php

@@ -132,7 +132,7 @@ public function getTitle(): ?string
         return $this->title;
     }
 
-    public function setTitle(string $title): void
+    public function setTitle(?string $title): void
     {
         $this->title = $title;
     }
@@ -152,7 +152,7 @@ public function getContent(): ?string
         return $this->content;
     }
 
-    public function setContent(string $content): void
+    public function setContent(?string $content): void
     {
         $this->content = $content;
     }
@@ -200,7 +200,7 @@ public function getSummary(): ?string
         return $this->summary;
     }
 
-    public function setSummary(string $summary): void
+    public function setSummary(?string $summary): void
     {
         $this->summary = $summary;
     }