gpperfmon: gpperfmon_install should include IPv6 localhost

If IPv6 is enabled, gpperfmon will complain that it can't connect to
the database because, gpmon does not have permission to access through
::1.

- Add behave test

gpAux/gpperfmon/src/gpmon/gpperfmon_install

@@ -166,6 +166,9 @@ if __name__ == '__main__':
         cmd = Command("""echo "host     all         gpmon         127.0.0.1/28    md5" >> %s""" % pg_hba, showOutput=True)
         commands.append(cmd)
 
+        cmd = Command("""echo "host     all         gpmon         ::1/128    md5" >> %s""" % pg_hba, showOutput=True)
+        commands.append(cmd)
+
         ################################################
         # these commands add a new line to the top of .pgpass and save a copy of old .pgpass
         cmd = Command("""touch %s""" % (pg_pass))

gpMgmt/test/behave/mgmt_utils/gpperfmon.feature

@@ -17,7 +17,8 @@ Feature: gpperfmon
         Given the database "gpperfmon" does not exist
         When the user runs "gpperfmon_install --port 15432 --enable --password foo"
         Then gpperfmon_install should return a return code of 0
-        Then verify that the last line of the master postgres configuration file contains the string "gpperfmon_log_alert_level=warning"
+        Then verify that the last line of the file "postgresql.conf" in the master data directory contains the string "gpperfmon_log_alert_level=warning"
+        Then verify that the last line of the file "pg_hba.conf" in the master data directory contains the string "host     all         gpmon         ::1/128    md5"
         And verify that there is a "heap" table "database_history" in "gpperfmon"
 
     @gpperfmon_run

gpMgmt/test/behave/mgmt_utils/steps/mgmt_utils.py

@@ -4213,11 +4213,11 @@ def impl(context, filename, output):
     check_stdout_msg(context, output)
 
 
-@then('verify that the last line of the master postgres configuration file contains the string "{output}"')
-def impl(context, output):
+@then('verify that the last line of the file "{filename}" in the master data directory contains the string "{output}"')
+def impl(context, filename, output):
     contents = ''
-    filename = master_data_dir + "/postgresql.conf"
-    with open(filename) as fr:
+    file_path = os.path.join(master_data_dir, filename)
+    with open(file_path) as fr:
         for line in fr:
             contents = line.strip()
     pat = re.compile(output)
@@ -4883,7 +4883,7 @@ def impl(context):
             When the user runs "gpstart -a"
             Then gpstart should return a return code of 0
             And verify that a role "gpmon" exists in database "gpperfmon"
-            And verify that the last line of the master postgres configuration file contains the string "gpperfmon_log_alert_level=warning"
+            And verify that the last line of the file "postgresql.conf" in the master data directory contains the string "gpperfmon_log_alert_level=warning"
             And verify that there is a "heap" table "database_history" in "gpperfmon"
             Then wait until the process "gpmmon" is up
             And wait until the process "gpsmon" is up