feat: update README.md status badges and improve TestFastEnforcer() (#396)

BREAKING CHANGE: this work for release PyCasbin v2

* docs: change status badge

fix: #395

* test: the performance test is fuzzy, measure multiple times and compare the average values.

* docs: Update README.md status badge

Author: wf-yamaday

README.md

@@ -1,12 +1,12 @@
 PyCasbin
 ====
 
-[![GitHub Action](https://github.com/casbin/pycasbin/workflows/build/badge.svg?branch=master)](https://github.com/casbin/pycasbin/actions)
+[![build](https://github.com/casbin/pycasbin/actions/workflows/build.yml/badge.svg)](https://github.com/casbin/pycasbin/actions/workflows/build.yml)
 [![Coverage Status](https://coveralls.io/repos/github/casbin/pycasbin/badge.svg)](https://coveralls.io/github/casbin/pycasbin)
 [![Version](https://img.shields.io/pypi/v/pycasbin.svg)](https://pypi.org/project/pycasbin/)
 [![PyPI - Wheel](https://img.shields.io/pypi/wheel/pycasbin.svg)](https://pypi.org/project/pycasbin/)
 [![Pyversions](https://img.shields.io/pypi/pyversions/pycasbin.svg)](https://pypi.org/project/pycasbin/)
-[![Download](https://img.shields.io/pypi/dm/pycasbin.svg)](https://pypi.org/project/pycasbin/)
+[![Download](https://static.pepy.tech/badge/pycasbin)](https://pypi.org/project/pycasbin/)
 [![Discord](https://img.shields.io/discord/1022748306096537660?logo=discord&label=discord&color=5865F2)](https://discord.gg/S5UjpzGZjN)
 
 <p align="center">

tests/test_fast_enforcer.py

@@ -46,13 +46,19 @@ def test_performance(self) -> None:
             get_examples("performance/rbac_with_pattern_large_scale_policy.csv"),
             [2, 1],
         )
-        s_e1 = time.perf_counter()
-        e1.enforce("alice", "data1", "read")
-        t_e1 = time.perf_counter() - s_e1
-        s_e2 = time.perf_counter()
-        e2.enforce("alice", "data1", "read")
-        t_e2 = time.perf_counter() - s_e2
-        assert t_e1 > t_e2 * 5
+        N = 5
+        t_e1_list = []
+        t_e2_list = []
+        for _ in range(N):
+            s_e1 = time.perf_counter()
+            e1.enforce("alice", "data1", "read")
+            t_e1_list.append(time.perf_counter() - s_e1)
+            s_e2 = time.perf_counter()
+            e2.enforce("alice", "data1", "read")
+            t_e2_list.append(time.perf_counter() - s_e2)
+        avg_t_e1 = sum(t_e1_list) / N
+        avg_t_e2 = sum(t_e2_list) / N
+        assert avg_t_e1 > avg_t_e2 * 5
 
     def test_creates_proper_policy(self) -> None:
         e = self.get_enforcer(