Update opening_brace for multiline if statements

[Juice805]

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Rule update request

Similar to #3068 I'd like to propose a change to opening_brace to allow the following format:

if let child = parent.children.first,
    let grandchild = child.children.first,
    let greatGrandchild = grandchild.children.first
{
    // Some code
}

or

if 
    let child = parent.children.first,
    let grandchild = child.children.first,
    let greatGrandchild = grandchild.children.first
{
    // Some code
}

Currently the autocorrect will fix it to the following which is difficult to read:

if 
    let child = parent.children.first,
    let grandchild = child.children.first,
    let greatGrandchild = grandchild.children.first {
    // Some code
}

[Juice805]

looks like while also has this issue and should be included:

while 
    let child = parent.children.first,
    let grandchild = child.children.first,
    let greatGrandchild = grandchild.children.first
{
    // Some code
}

guard does not assuming this structure:

guard
    let child = parent.children.first,
    let grandchild = child.children.first,
    let greatGrandchild = grandchild.children.first
else {
    // Some code
}