minor #20497 [Validator] Cannot validate svg image size (MrYamous)

This PR was merged into the 6.4 branch.

Discussion
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[Validator] Cannot validate svg image size

As an addition of #20496 and considering what is described in related [code PR](symfony/symfony#59265) I think it can be helpful to explicit mention this restriction for SVG images

Commits
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248d4ff cannot validate svg image size

Author: javiereguiluz

reference/constraints/Image.rst

@@ -530,5 +530,10 @@ options has been set.
 
 This message has no parameters.
 
+.. note::
+
+    SVG images sizes are not currently supported. Using size constraints with
+    these files will display this message.
+
 .. _`IANA website`: https://www.iana.org/assignments/media-types/media-types.xhtml
 .. _`PHP GD extension`: https://www.php.net/manual/en/book.image.php