update format

Author: Anup Kumar

tools/tabpfn/tabpfn.xml

@@ -48,7 +48,7 @@
                 </param>
             </when>
             <when value="upload">
-                <param name="model_checkpoint" type="data" format=".ckpt"
+                <param name="model_checkpoint" type="data" format="ckpt"
                 label="Custom Model Checkpoint"
                 help="Upload a model checkpoint file containing the TabPFN model." />
             </when>