Added poetry integration.

Description:
* Fixed github actions;
* Removed requirements.txt;
* Fixed CONTRIBUTING.md;
* Fixed black and flake8.

Signed-off-by: Pavel <win10@list.ru>

.vscode/settings.json

@@ -0,0 +1,5 @@
+{
+    "python.linting.flake8Enabled": true,
+    "python.linting.enabled": true,
+    "python.formatting.provider": "black"
+}