Fix _test database name when using query strings

If your DB connection string had 1 or more query strings the test
database name was being appended at the end of the URL instead of
after the database name itself.

Old (broken) behavior:
  myapp?encoding=utf8_test

New (fixed) behavior:
  myapp_test?encoding=utf8

CHANGELOG.md

@@ -42,6 +42,10 @@ Changelog](https://keepachangelog.com/en/1.0.0/).
 - Update `postcss-import` to `15.0.0`
 - Update `postcss` to `8.4.17`
 
+### Fixed
+
+- Correctly append `_test` database name to database URI when using query strings
+
 ## [0.10.0] - 2022-09-08
 
 ### Added

test/conftest.py

@@ -12,7 +12,13 @@ def app():
 
     :return: Flask app
     """
-    db_uri = f"{settings.SQLALCHEMY_DATABASE_URI}_test"
+    db_uri = settings.SQLALCHEMY_DATABASE_URI
+
+    if "?" in db_uri:
+        db_uri = db_uri.replace("?", "_test?")
+    else:
+        db_uri = f"{db_uri}_test"
+
     params = {
         "DEBUG": False,
         "TESTING": True,