Bump pytest-asyncio from 0.14.0 to 0.15.1 (#27)

Bumps [pytest-asyncio](https://github.com/pytest-dev/pytest-asyncio) from 0.14.0 to 0.15.1.
- [Release notes](https://github.com/pytest-dev/pytest-asyncio/releases)
- [Commits](pytest-dev/pytest-asyncio@v0.14.0...v0.15.1)

Signed-off-by: dependabot[bot] <[email protected]>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

poetry.lock

@@ -30,7 +30,7 @@ black = "^21.5b2"
 
 # tests
 pytest = "^6.2.4"
-pytest-asyncio = "^0.14.0"
+pytest-asyncio = "^0.15.1"
 pytest-cov = "^2.12.1"
 
 [tool.poetry.plugins."gino.extensions"]