Rewriter: Convert to `tag.pre`

Converting from `<pre></pre>` to `tag.pre` results in odd syntax:

**Input:**
```erb
    <pre><%= foo %></pre>
```

**Output:**
```erb
    <%= tag.pre do %><%= foo %><% end %>
```

**Expected:**
```erb
    <%= tag.pre(foo) %>
```

Although the `do`/`end` format does work, it seems very strange. I'd expect it to be a positional argument instead.