Drop use of the vendored dependencies

Fixes: oracle#444

Author: pabs3

docs/new-region-support.rst

@@ -42,4 +42,4 @@ If you are authenticating via instance principals, you can set the federation_en
 
 If the correct federation_endpoint for the region is not passed in, you will see the following error during instance principals authentication::
     
-    oci._vendor.requests.exceptions.ConnectionError: HTTPSConnectionPool(host='auth.us-gov-phoenix-1.oraclecloud.com', port=443): Max retries exceeded with url: /v1/x509 (Caused by NewConnectionError('<oci._vendor.urllib3.connection.VerifiedHTTPSConnection object at 0x7f5c91002ba8>: Failed to establish a new connection: [Errno -2] Name or service not known',))
+    requests.exceptions.ConnectionError: HTTPSConnectionPool(host='auth.us-gov-phoenix-1.oraclecloud.com', port=443): Max retries exceeded with url: /v1/x509 (Caused by NewConnectionError('<urllib3.connection.VerifiedHTTPSConnection object at 0x7f5c91002ba8>: Failed to establish a new connection: [Errno -2] Name or service not known',))

examples/object_crud.py

@@ -8,7 +8,7 @@
 import pytz
 
 import oci
-from oci._vendor import urllib3
+import urllib3
 from oci.object_storage.models import CreateBucketDetails
 from oci.object_storage.models import CreatePreauthenticatedRequestDetails
 

setup.cfg

@@ -9,9 +9,8 @@ exclude =
     __pycache__,
     docs/conf.py,
     build,
-    dist,
-    src/oci/_vendor
-max_line_length = 99
+    dist
+max-line-length = 99
 
 [metadata]
-license_files = LICENSE.txt THIRD_PARTY_LICENSES.txt
+license-files = LICENSE.txt THIRD_PARTY_LICENSES.txt