Use get_eol_chars utility function added to python-lsp-server 1.4.0

Also drop support for Python 3.6 because that version of
python-lsp-server only supports 3.7+

Author: ccordoba12

pylsp_black/_utils.py

@@ -7,7 +7,7 @@
 import toml
 from pylsp import hookimpl
 
-from pylsp_black._utils import get_eol_chars
+from pylsp._utils import get_eol_chars
 
 logger = logging.getLogger(__name__)
 

pylsp_black/plugin.py

@@ -18,8 +18,8 @@ classifiers =
 
 [options]
 packages = find:
-install_requires = python-lsp-server; black>=19.3b0; toml
-python_requires = >= 3.6
+install_requires = python-lsp-server>=1.4.0; black>=19.3b0; toml
+python_requires = >= 3.7
 
 [options.entry_points]
 pylsp = pylsp_black = pylsp_black.plugin