Tests: use datetime.timezone.utc instead of datetime.UTC.

sasozivanovic · sasozivanovic · commit 86b33f3a9d69 · 2026-03-29T07:30:50.000+02:00
`datetime.UTC` was only introduced in Python 3.11, so the CIs were failing on
setups with Python 3.10.
diff --git a/src/trio/_tests/test_ssl.py b/src/trio/_tests/test_ssl.py
@@ -567,7 +567,7 @@ def client() -> None:
 
     # An expired client certificate: this should fail
     client_cert = TRIO_TEST_CA.issue_cert(
-        "user@example.org", not_after=datetime.datetime.now(datetime.UTC)
+        "user@example.org", not_after=datetime.datetime.now(datetime.timezone.utc)
     )
     client_cert.configure_cert(client_ctx)
 

Original file line number	Diff line number	Diff line change
`@@ -567,7 +567,7 @@ def client() -> None:`
`567`	`567`
`568`	`568`	`# An expired client certificate: this should fail`
`569`	`569`	`client_cert = TRIO_TEST_CA.issue_cert(`
`570`		`- "user@example.org", not_after=datetime.datetime.now(datetime.UTC)`
	`570`	`+ "user@example.org", not_after=datetime.datetime.now(datetime.timezone.utc)`
`571`	`571`	`)`
`572`	`572`	`client_cert.configure_cert(client_ctx)`
`573`	`573`