Copyright line should append after the SPDX identifier

I just tried SPDX flag first time and noticed addlicense adds _copyright_ line before the SPDX identifier.

```
$ addlicense -s=only -c Furkan .
```

Actual:
```
Copyright ...
SPDX-License-Identifier:
```

My expectation according to other open source projects, solidity, etc.:
```
SPDX-License-Identifier:
Copyright ...
```

Any ways to reorder of those? Shouldn't the right way is the bottom one?

Start by tracing the addlicense command with the -s=only flag through the header-generation logic. Confirm how the SPDX identifier and copyright line are ordered, then verify that generated headers consistently place SPDX first and copyright second.

Written by the indexing model from the issue text.