`lines_before_import` adds newlines above module's docstring when used with `float_to_top`

[gbolmier]

Using MacOS, python 3.7.11, isort 5.10.1, and the following config in pyproject.toml:

[tool.isort]
lines_before_imports = 1
float_to_top = true

Before running isort tmp.py:

"""
Tmp module.
"""
import os
os.getcwd()

After:

  
"""
Tmp module.
"""

import os

os.getcwd()

(note the added leading empty line)