Update bootstrap-table.js

After press Clear Filter button and clear filter input, the table view is not updated.
With this patch, the table view is update correctly after clearing filter.

src/bootstrap-table.js

@@ -724,7 +724,7 @@ class BootstrapTable {
         $(currentTarget).val(text)
       }
 
-      if (this.searchText === text) {
+      if (this.searchText === text && text.length > 0) {
         return
       }