[multi-asic]: remove load_sonic_global_db_config calls (#8173)

#### Why I did it
Remove the call to `SonicDBConfig.load_sonic_global_db_config()` in the multi asic functions.
The expection is the client calling this function will call `SonicDBConfig.load_sonic_global_db_config()`

This PR is dependent on the PR sonic-net/sonic-utilities#1712 
#### How to verify it
compile sonic-utilities

src/sonic-host-services/scripts/caclmgrd

@@ -18,7 +18,7 @@ try:
     import threading
     import time
 
-    from sonic_py_common import daemon_base, device_info
+    from sonic_py_common import daemon_base, device_info, multi_asic
     from swsscommon import swsscommon
 except ImportError as err:
     raise ImportError("%s - required module not found" % str(err))
@@ -108,7 +108,7 @@ class ControlPlaneAclManager(daemon_base.DaemonBase):
         self.namespace_docker_mgmt_ip = {}
         self.namespace_docker_mgmt_ipv6 = {}
 
-        namespaces = device_info.get_all_namespaces()
+        namespaces = multi_asic.get_all_namespaces()
         for front_asic_namespace in namespaces['front_ns']:
             self.update_thread[front_asic_namespace] = None
             self.lock[front_asic_namespace] = threading.Lock()

src/sonic-py-common/sonic_py_common/multi_asic.py

@@ -3,9 +3,7 @@
 import subprocess
 
 from natsort import natsorted
-from swsssdk import ConfigDBConnector
-from swsssdk import SonicDBConfig
-from swsssdk import SonicV2Connector
+from swsscommon import swsscommon
 
 from .device_info import CONTAINER_PLATFORM_PATH
 from .device_info import HOST_DEVICE_PATH
@@ -39,8 +37,7 @@ def connect_config_db_for_ns(namespace=DEFAULT_NAMESPACE):
     Returns:
       handle to the config_db for a namespace
     """
-    SonicDBConfig.load_sonic_global_db_config()
-    config_db = ConfigDBConnector(namespace=namespace)
+    config_db = swsscommon.ConfigDBConnector(namespace=namespace)
     config_db.connect()
     return config_db
 
@@ -58,8 +55,7 @@ def connect_to_all_dbs_for_ns(namespace=DEFAULT_NAMESPACE):
     Returns:
         handle to all the dbs for a namespaces
     """
-    SonicDBConfig.load_sonic_global_db_config()
-    db = SonicV2Connector(namespace=namespace)
+    db = swsscommon.SonicV2Connector(namespace=namespace)
     for db_id in db.get_db_list():
         db.connect(db_id)
     return db