Fix jumping form by setting min-height to error element

Author: TheZoker

src/index.tsx

@@ -10,10 +10,15 @@ const theme = createTheme({
     MuiFormControl: {
       styleOverrides: {
         root: {
-          margin: '0.8em 0',
+            margin: '0.3em 0',
         },
       }
     },
+    MuiFormHelperText: {
+      root: {
+        minHeight: '1.6em'
+      }
+    }
   },
 });