Pin to isort 5

Author: pquentin

noxfile.py

@@ -66,7 +66,9 @@ def test_otel(session):
 
 @nox.session()
 def format(session):
-    session.install(".", "black~=25.0", "isort", "flynt", "unasync>=0.6.0", "jinja2")
+    session.install(
+        ".", "black~=25.0", "isort<6", "flynt", "unasync>=0.6.0", "jinja2"
+    )
 
     session.run("python", "utils/run-unasync.py")
     session.run("python", "utils/run-unasync-dsl.py")
@@ -90,7 +92,7 @@ def lint(session):
         "flake8",
         "black~=25.0",
         "mypy",
-        "isort",
+        "isort<6",
         "types-requests",
         "types-python-dateutil",
         "unasync>=0.6.0",