Assignment to long attribute name (or attrset) of appended local path doesn't indent new line

[jmholla]

Description

When assigning an appended to long path with a very long left hand operand, the concatenating string is placed on a new line without an indentation.

Small example input

let
  aLongVariableNameOrEvenDeepAttrsetGettingAssignedAnAppendedToLocalPath = ./. + "some/string/path/that/forces/a/wrap/to/happen";
in "example"

Expected output

let
  aLongVariableNameOrEvenDeepAttrsetGettingAssignedAnAppendedToLocalPath = ./.
    + "some/string/path/that/forces/a/wrap/to/happen";
in
"example"

Actual output

let
  aLongVariableNameOrEvenDeepAttrsetGettingAssignedAnAppendedToLocalPath = ./.
  + "some/string/path/that/forces/a/wrap/to/happen";
in
"example"