python312Packages.aws-sam-translator: don't fail when pytest/pluggy, skip slow tests

eg:
python3.12-aws-sam-translator>   File "/nix/store/jzba2jjz0l3222pry5mf6nyflbwgpd32-python3.12-python-dateutil-2.8.2/lib/python3.12/site-packages/dateutil/tz/__init__.py", line 2, in <module>
python3.12-aws-sam-translator>     from .tz import *
python3.12-aws-sam-translator>   File "/nix/store/jzba2jjz0l3222pry5mf6nyflbwgpd32-python3.12-python-dateutil-2.8.2/lib/python3.12/site-packages/dateutil/tz/tz.py", line 37, in <module>
python3.12-aws-sam-translator>     EPOCH = datetime.datetime.utcfromtimestamp(0)
python3.12-aws-sam-translator>             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
python3.12-aws-sam-translator> DeprecationWarning: datetime.datetime.utcfromtimestamp() is deprecated and scheduled for removal in a future version. Use timezone-aware objects to represent datetimes in UTC: datetime.datetime.fromtimestamp(timestamp, datetime.UTC).
python3.12-aws-sam-translator>

pkgs/development/python-modules/aws-sam-translator/default.nix

@@ -29,8 +29,8 @@ buildPythonPackage rec {
   };
 
   postPatch = ''
-    substituteInPlace pytest.ini \
-      --replace " --cov samtranslator --cov-report term-missing --cov-fail-under 95" ""
+    # don't try to use --cov or fail on new warnings
+    rm pytest.ini
   '';
 
   propagatedBuildInputs = [
@@ -49,14 +49,15 @@ buildPythonPackage rec {
     pyyaml
   ];
 
-  pythonImportsCheck = [
-    "samtranslator"
-  ];
-
   preCheck = ''
-    sed -i '2ienv =\n\tAWS_DEFAULT_REGION=us-east-1' pytest.ini
+    export AWS_DEFAULT_REGION=us-east-1
   '';
 
+  pytestFlagsArray = [
+    "tests"
+    ''-m "not slow"''
+  ];
+
   disabledTests = [
     # urllib3 2.0 compat
     "test_plugin_accepts_different_sar_client"
@@ -79,6 +80,10 @@ buildPythonPackage rec {
 
   __darwinAllowLocalNetworking = true;
 
+  pythonImportsCheck = [
+    "samtranslator"
+  ];
+
   meta = with lib; {
     description = "Python library to transform SAM templates into AWS CloudFormation templates";
     homepage = "https://github.com/aws/serverless-application-model";