Bump curio from 1.4 to 1.5

Bumps [curio](https://github.com/dabeaz/curio) from 1.4 to 1.5.
- [Release notes](https://github.com/dabeaz/curio/releases)
- [Changelog](https://github.com/dabeaz/curio/blob/master/CHANGES)
- [Commits](dabeaz/curio@1.4...1.5)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Author: dependabot-preview[bot]

poetry.lock

@@ -60,7 +60,7 @@ typing-extensions = "^3.7"
 
 [tool.poetry.dev-dependencies]
 anyio = "^2.2"
-curio = "^1.4"
+curio = "^1.5"
 trio = "^0.18"
 attrs = "^20.3"
 httpx = "^0.17"