change(aurweb): add parallel tests and improve aurweb.db

This change utilizes pytest-xdist to perform a multiproc test
run and reworks aurweb.db's code. We no longer use a global
engine, session or Session, but we now use a memo of engines
and sessions as they are requested, based on the PYTEST_CURRENT_TEST
environment variable, which is available during testing.

Additionally, this change strips several SQLite components
out of the Python code-base.

SQLite is still compatible with PHP and sharness tests, but
not with our FastAPI implementation.

More changes:
------------
- Remove use of aurweb.db.session global in other code.
- Use new aurweb.db.name() dynamic db name function in env.py.
- Added 'addopts' to pytest.ini which utilizes multiprocessing.
    - Highly recommended to leave this be or modify `-n auto` to
      `-n {cpu_threads}` where cpu_threads is at least 2.

Signed-off-by: Kevin Morris <kevr@0cost.org>

test/test_accepted_term.py

@@ -2,38 +2,33 @@ import pytest
 
 from sqlalchemy.exc import IntegrityError
 
-from aurweb.db import create, query
+from aurweb import db
 from aurweb.models.accepted_term import AcceptedTerm
-from aurweb.models.account_type import AccountType
+from aurweb.models.account_type import USER_ID
 from aurweb.models.term import Term
 from aurweb.models.user import User
-from aurweb.testing import setup_test_db
 
 user = term = accepted_term = None
 
 
 @pytest.fixture(autouse=True)
-def setup():
-    global user, term, accepted_term
+def setup(db_test):
+    global user, term
 
-    setup_test_db("Users", "AcceptedTerms", "Terms")
+    with db.begin():
+        user = db.create(User, Username="test", Email="test@example.org",
+                         RealName="Test User", Passwd="testPassword",
+                         AccountTypeID=USER_ID)
 
-    account_type = query(AccountType,
-                         AccountType.AccountType == "User").first()
-    user = create(User, Username="test", Email="test@example.org",
-                  RealName="Test User", Passwd="testPassword",
-                  AccountType=account_type)
-
-    term = create(Term, Description="Test term", URL="https://test.term")
+        term = db.create(Term, Description="Test term",
+                         URL="https://test.term")
 
     yield term
 
-    # Eradicate any terms we created.
-    setup_test_db("AcceptedTerms", "Terms")
-
 
 def test_accepted_term():
-    accepted_term = create(AcceptedTerm, User=user, Term=term)
+    with db.begin():
+        accepted_term = db.create(AcceptedTerm, User=user, Term=term)
 
     # Make sure our AcceptedTerm relationships got initialized properly.
     assert accepted_term.User == user
@@ -42,14 +37,10 @@ def test_accepted_term():
 
 
 def test_accepted_term_null_user_raises_exception():
-    from aurweb.db import session
     with pytest.raises(IntegrityError):
-        create(AcceptedTerm, Term=term)
-    session.rollback()
+        AcceptedTerm(Term=term)
 
 
 def test_accepted_term_null_term_raises_exception():
-    from aurweb.db import session
     with pytest.raises(IntegrityError):
-        create(AcceptedTerm, User=user)
-    session.rollback()
+        AcceptedTerm(User=user)