[vulkan] Set kApiVersion to VK_API_VERSION_1_3

This change fixes issue #4900. On certain AMD GPUs (such as RX 5500),
the Vullkan version needs to be 1.3 in order for Volk to correctly populate
the "vkGetDeviceBufferMemoryRequirements" function pointer. If the
version is 1.2, the pointer will be NULL and cause an assertion failure.

Tested by running the voxel challenge program and see the program
working as expected on a Windows PC.

taichi/backends/vulkan/vulkan_utils.h

@@ -22,7 +22,7 @@ namespace vulkan {
 class VulkanEnvSettings {
  public:
   static constexpr uint32_t kApiVersion() {
-    return VK_API_VERSION_1_2;
+    return VK_API_VERSION_1_3;
   }
 };