[Mobile/React_Native] Fix the model input rank used in the expo app (#321)

* fix the model input rank used in the app

* fix the model input name for qa sample

---------

Co-authored-by: rachguo <[email protected]>
Co-authored-by: rachguo <[email protected]>

Author: 3 people

mobile/examples/React_Native/ort-rn-basic-usage/App.tsx

@@ -42,7 +42,7 @@ async function runModel() {
     // Note: In real use case, you must set the inputData to the actual input values
     const inputData = new Float32Array(28 * 28);
     const feeds:Record<string, ort.Tensor> = {};
-    feeds[myModel.inputNames[0]] = new ort.Tensor(inputData, [1, 28, 28]);
+    feeds[myModel.inputNames[0]] = new ort.Tensor(inputData, [1, 1, 28, 28]);
     // Run inference session
     const fetches = await myModel.run(feeds);
     // Process output

mobile/examples/question_answering/android/app/src/main/java/ai/onnxruntime/example/question_answering/MainActivity.kt

@@ -111,7 +111,7 @@ class MainActivity : AppCompatActivity() {
     }
 
     private fun readModel(): ByteArray {
-        val modelID = R.raw.mobilebert_quant_with_pre_post_processing
+        val modelID = R.raw.csarron_mobilebert_uncased_squad_v2_quant_with_pre_post_processing
         return resources.openRawResource(modelID).readBytes()
     }