Update is-supported-image-removed.md (#2214)

Author: innerdvations

docusaurus/docs/dev-docs/migration/v4-to-v5/breaking-changes/is-supported-image-removed.md

@@ -41,7 +41,7 @@ The `isSupportedImage` method is supported, but deprecated.
 
 The `isSupportedImage` method is removed.
 
-Developers must use either `isImage` to check if a file is an image, or `isOptimizableImage` to check if the file is an image that can be optimized.
+Developers must use either `isImage` to check if a file is an image, or `isOptimizableImage` to check if the file is an image that can be optimized. Note that the behavior in Strapi v4 was equivalent to `isOptimizableImage`.
 
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