Add a direct dependency on yarl to instrumentaton-aiohttp-client

The minimum version ensures the expected URL string in the tests is
consistent; see
open-telemetry#1772.

The yarl dependency is needed both for the package and for the tests.

instrumentation/opentelemetry-instrumentation-aiohttp-client/pyproject.toml

@@ -30,6 +30,7 @@ dependencies = [
   "opentelemetry-semantic-conventions == 0.40b0.dev",
   "opentelemetry-util-http == 0.40b0.dev",
   "wrapt >= 1.0.0, < 2.0.0",
+  "yarl >= 1.9.1",
 ]
 
 [project.optional-dependencies]