[clang-format] Add AfterComma option for BreakConstructorInitializers (#180541)
This patch introduces a new `AfterComma` value for the
`BreakConstructorInitializers` style option. This style keeps the
constructor initializer colon on the same line as the constructor
declaration and breaks after each comma in the initializer list.
Example formatting:
```cpp
Constructor() : initializer1(),
initializer2()
```
This style provides an alternative to the existing BeforeColon,
BeforeComma, and AfterColon options, allowing developers to maintain the
colon on the constructor line while placing each initializer on its own
line after commas.
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Co-authored-by: Perceval <perceval@trilogic.fr>