fix: pip pinned to 19.3.1 after v20 breaking

reference: https://github.com/pypa/pip/issues/7217

.circleci/config.yml

@@ -7,7 +7,7 @@ jobs:
       - checkout
       - run:
           name: Setup
-          command: |            
+          command: |
             sudo pip install --ignore-installed setuptools
             sudo pip install urllib3 pyOpenSSL ndg-httpsclient pyasn1
             sudo cp -r ~/.ssh/* /root/.ssh
@@ -24,7 +24,7 @@ jobs:
           name: Setup Tests
           command: |
             cd ~
-            sudo pip install --upgrade pip
+            sudo pip install --upgrade pip==19.3.1
             sudo pip install -e ~/.bench
 
       - run:

.travis.yml

@@ -20,7 +20,7 @@ install:
 
 script:
   - cd ~
-  - sudo pip install --upgrade pip
+  - sudo pip install --upgrade pip==19.3.1
   - sudo pip install -e ~/.bench
   # - sudo python -m unittest bench.tests.test_setup_production.TestSetupProduction.test_setup_production_v6
   - sudo python -m unittest -v bench.tests.test_setup_production

bench/utils.py

@@ -203,7 +203,7 @@ def setup_env(bench_path='.', python = 'python3'):
 	pip    = os.path.join('env', 'bin', 'pip')
 
 	exec_cmd('virtualenv -q {} -p {}'.format('env', python), cwd=bench_path)
-	exec_cmd('{} -q install -U pip wheel six'.format(pip), cwd=bench_path)
+	exec_cmd('{} -q install -U pip==19.3.1 wheel six'.format(pip), cwd=bench_path)
 	exec_cmd('{} -q install -e git+https://github.com/frappe/python-pdfkit.git#egg=pdfkit'.format(pip), cwd=bench_path)
 
 def setup_socketio(bench_path='.'):