Fix for CanRead function for FBXImporter (#6158)

* Fixed CanRead function for FBXImporter, which is important when reading from memory

* Update FBXImporter.cpp

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Co-authored-by: Kim Kulling <kimkulling@users.noreply.github.com>

code/AssetLib/FBX/FBXImporter.cpp

@@ -90,7 +90,7 @@ namespace {
 // Returns whether the class can handle the format of the given file.
 bool FBXImporter::CanRead(const std::string & pFile, IOSystem * pIOHandler, bool /*checkSig*/) const {
 	// at least ASCII-FBX files usually have a 'FBX' somewhere in their head
-	static const char *tokens[] = { " \n\r\n " };
+	static const char *tokens[] = { " \n\r\n ", "fbx" };
 	return SearchFileHeaderForToken(pIOHandler, pFile, tokens, AI_COUNT_OF(tokens));
 }