{CI} Fix top N slowest Test

[wangzelin007]

Description

This PR will speed up our test.

• Our list command is not pagination, it will get all the data.
  That is why some recording files are very large.
  And in test_show_built_in_policy, we choose to check the first resource instead of check all the resource to speed up.

• We only mock time.sleep in azure-sdk-tools.
  That's why if someone use sleep(xxx), it will not work.
  

  azure-cli/src/azure-cli-testsdk/azure/cli/testsdk/scenario_tests/patches.py

  Line 13 in 30216d0

  mock_in_unit_test(unit_test, 'time.sleep', _time_sleep_skip)

Profile	Test Case	Before	After	Total saving time
Latest	test_show_built_in_policy	536.57s	2.94s
2019-03-01	test_show_built_in_policy	210.69s	3.01s
Latest	test_sql_db_restore	305.01s	8.70s
Latest	test_sql_db_restore_deleted	184.63s	7.39s
Latest	test_postgrsql_general_purpose_replica_mgmt	121.76s	4.11s
Latest	test_sql_tde	10.54s	3.03s
Latest	test_sql_ledger	7.62s	3.00s
Total				1,344.64s

Testing Guide

History Notes

[Component Name 1] BREAKING CHANGE: az command a: Make some customer-facing breaking change
[Component Name 2] az command b: Add some customer-facing feature

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[yonzhan]

CI

[jiasli]

from time import sleep can now be removed.

[wangzelin007]

We need modify these codes before remove from time import sleep.
I think add if self.is_live condition is also acceptable.

azure-cli/src/azure-cli/azure/cli/command_modules/sql/tests/latest/test_sql_commands.py

Lines 1125 to 1126 in 92e4524

	if self.is_live:
	sleep(120)

azure-cli/src/azure-cli/azure/cli/command_modules/sql/tests/latest/test_sql_commands.py

Lines 1454 to 1456 in 92e4524

	if self.is_live:
	self.assertTrue(datetime.now() < start_time + timeout, 'Deleted db not found before timeout expired.')
	sleep(10) # seconds

azure-cli/src/azure-cli/azure/cli/command_modules/sql/tests/latest/test_sql_commands.py

Lines 2743 to 2744 in 92e4524

	if self.is_live:
	sleep(120)

azure-cli/src/azure-cli/azure/cli/command_modules/sql/tests/latest/test_sql_commands.py

Lines 2764 to 2765 in 92e4524

	if self.is_live:
	sleep(60)

azure-cli/src/azure-cli/azure/cli/command_modules/sql/tests/latest/test_sql_commands.py

Lines 2777 to 2778 in 92e4524

	if self.is_live:
	sleep(60)

azure-cli/src/azure-cli/azure/cli/command_modules/sql/tests/latest/test_sql_commands.py

Lines 4481 to 4482 in 92e4524

	if self.is_live:
	sleep(120)

azure-cli/src/azure-cli/azure/cli/command_modules/sql/tests/latest/test_sql_commands.py

Lines 4594 to 4595 in 92e4524

	if self.is_live:
	sleep(120)

azure-cli/src/azure-cli/azure/cli/command_modules/sql/tests/latest/test_sql_commands.py

Lines 4607 to 4608 in 92e4524

	if self.is_live:
	sleep(120)

[jiasli]

Let's only remove from time import sleep when it is not used.