Let users upgrade pip if and when they want

Rationale: pypa/pip#9011

Author: Cheaterman

run.py

@@ -12,18 +12,6 @@
 WSGI_MODULE = os.environ.get('WSGI_MODULE', 'app:app')
 
 os.chdir('/code')
-subprocess.run([
-    'su',
-    'uwsgi',
-    '-c',
-    ' '.join((
-        'pip',
-        'install',
-        '--no-cache-dir',
-        '--upgrade',
-        'pip',
-    )),
-], check=True)
 subprocess.run([
     'su',
     'uwsgi',