Specify the cacert file in the verify option when in secure mode

When running in secure mode we want to set the "verify"
option to the path to the cacert file

Tests:
1° I generate a certificate using the documentation and installed on the
controller (activate https), I got the ca cert and I set up a remote
cli pointing to a DC and I exported the certificate in a variable
OS_CACERT to the client get it, I ran some commands from DC.
2° I passed a flag insecure to execute the dcmanager client
in a insecure mode
3° Built an ISO to check if something broke and installed on DC using
VDM to check if the dcmanager keeps the current behavior

Note: I think is a good ideia to plan a standardization of the clients
mainly the keystone (authentication) part

This change is based on the documentation of the requests documentation
https://docs.python-requests.org/en/master/user/advanced/#ssl-cert-verification

Closes-bug: 1927723
Signed-off-by: Rafael Jordão Jardim <RafaelJordao.Jardim@windriver.com>
Change-Id: I4221657b97592b319b3fbf54b5b8c6d325ec9aa3

distributedcloud-client/dcmanagerclient/api/httpclient.py

@@ -61,8 +61,10 @@ class HTTPClient(object):
                 LOG.warning('Client is set to not verify even though '
                             'cacert is provided.')
 
-            self.ssl_options['verify'] = not insecure
-            self.ssl_options['cert'] = cacert
+            if insecure:
+                self.ssl_options['verify'] = False
+            else:
+                self.ssl_options['verify'] = True if not cacert else cacert
 
     @log_request
     def get(self, url, headers=None):