Clang-Format: Allow empty functions to be single-line

For example

```
OIIOOutputDriver::~OIIOOutputDriver()
{
}
```

becomes

```
OIIOOutputDriver::~OIIOOutputDriver() {}
```

Saves quite some vertical space, which is especially handy for
constructors.

Pull Request: https://projects.blender.org/blender/blender/pulls/105594

.clang-format

@@ -130,7 +130,7 @@ PenaltyReturnTypeOnItsOwnLine: 10000
 #
 PenaltyBreakAssignment: 100
 
-AllowShortFunctionsOnASingleLine: None
+AllowShortFunctionsOnASingleLine: Empty
 
 SortIncludes: true