missing "=" sign at main.tf.j2

jinja2 template missing "=" at https://github.com/AjiArya/python-tfgen/blob/main/templates/main.tf.j2#L78 causing error:

```
Error: Unsupported block type

  on main.tf line 42, in resource "libvirt_domain" "ahs-vm2":
  42:     cpu {
```
the correct one is
```
    cpu = {
        mode = "host-passthrough"
    }
```
tested on btech lab