[#104] s3local: Use default HTTP client instead of requests

`requests` lib is not default, so it can be unavailable.

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

scenarios/preset/resolve_containers_in_preset.py

@@ -2,7 +2,8 @@
 
 import argparse
 import json
-import requests
+import http.client
+import ssl
 
 parser = argparse.ArgumentParser()
 parser.add_argument('--endpoint', help='Endpoint of the S3 gateway')
@@ -16,10 +17,13 @@ def main():
 
     preset = json.loads(preset_text)
 
+    conn = http.client.HTTPSConnection(args.endpoint, context = ssl._create_unverified_context())
     containers = []
     for bucket in preset.get('buckets'):
-        resp = requests.head(f'{args.endpoint}/{bucket}', verify=False)
-        containers.append(resp.headers['X-Container-Id'])
+        conn.request("HEAD", f'/{bucket}')
+        response = conn.getresponse()
+        containers.append(response.getheader('X-Container-Id'))
+        response.read()
 
     preset['containers'] = containers
     with open(args.preset_file, 'w+') as f: