Throw exception when not use swsssdk in UT. (#126)

#### Why I did it
swsssdk been deprecated after 202205 branch, all use should switch to sonic-swss-common.

#### How I did it
Throw exception when load swsssdk for none UT usage.

#### How to verify it
Pass all UT.

#### Which release branch to backport (provide reason below if selected)

#### Description for the changelog
Throw exception when load swsssdk for none UT usage.

#### Link to config_db schema for YANG module changes

#### A picture of a cute animal (not mandatory but encouraged)

setup.py

@@ -9,6 +9,11 @@
     'hiredis>=0.1.4'
 ]
 
+console_scripts={
+    'sonic-db-load = swsssdk:sonic_db_dump_load',
+    'sonic-db-dump = swsssdk:sonic_db_dump_load',
+}
+
 setup(
     name='swsssdk',
     version='2.0.1',
@@ -26,12 +31,7 @@
     extras_require={
         'high_perf': high_performance_deps
     },
-    entry_points={
-        'console_scripts': [
-            'sonic-db-load = swsssdk:sonic_db_dump_load',
-            'sonic-db-dump = swsssdk:sonic_db_dump_load',
-        ],
-    },
+    entry_points={},
     classifiers=[
         'Intended Audience :: Developers',
         'Operating System :: Linux',

src/swsssdk/__init__.py

@@ -1,12 +1,20 @@
 """
 Utility library for Switch-state Redis database access and syslog reporting.
 """
+import sys
 import logging
 
 logger = logging.getLogger(__name__)
 logger.setLevel(logging.INFO)
 logger.addHandler(logging.NullHandler())
 
+if ('unittest' not in sys.modules.keys() and
+        'mockredis' not in sys.modules.keys() and
+        'mock' not in sys.modules.keys()):
+    msg = "sonic-py-swsssdk been deprecated, please switch to sonic-swss-common."
+    logger.exception(msg)
+    raise ImportError("sonic-py-swsssdk been deprecated, please switch to sonic-swss-common.")
+
 try:
     from .dbconnector import SonicDBConfig, SonicV2Connector
     from .configdb import ConfigDBConnector, ConfigDBPipeConnector

test/test_moduleLoad.py

@@ -5,7 +5,7 @@
 sys.path.insert(0, os.path.join(modules_path, 'src'))
 
 from unittest import TestCase
-
+import subprocess
 
 class Test_load_sonic_db_config(TestCase):
     def test__db_map_attributes(self):
@@ -34,3 +34,10 @@ def test__dbConfig(self):
         for namespace in list(dbConfig.get_ns_list()):
             self.assertEqual(dbConfig.get_dbid('PFC_WD_DB', namespace), 5)
             self.assertEqual(dbConfig.get_dbid('APPL_DB', namespace), 0)
+
+def test_BlockUseSwsssdk():
+    # Import swsssdk will throw exception with deprecated message.
+    swsssdk_path = os.path.join(modules_path, 'src')
+    result = subprocess.run(["python", "-c", "import swsssdk;exit()"], capture_output=True, cwd=swsssdk_path)
+
+    assert "deprecated" in result.stderr.decode("utf-8")