fix_power_op_line_length preview style

[MichaReiser]

Implement Black's fix_power_op_line_length style as a preview style in Ruff.

b = 1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1**1

Should be formatted to

b = (
    1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
    ** 1
)

Notice the whitespace around the power op which we currently omit. This likely requires using if_group_breaks to only show the whitespace when the group breaks.