Remove exceptions for GetAtts to SGs (#3927)

Author: kddejong

src/cfnlint/rules/functions/GetAttFormat.py

@@ -24,8 +24,8 @@ def __init__(self):
         self.parent_rules = ["E1010"]
         self._exceptions = [
             # Need to measure for completeness of automation
-            "AWS::EC2::SecurityGroup.GroupId",
-            "AWS::EC2::SecurityGroup.GroupIds",
+            # "AWS::EC2::SecurityGroup.GroupId",
+            # "AWS::EC2::SecurityGroup.GroupIds",
         ]
         self._resource_type_exceptions = [
             "AWS::CloudFormation::CustomResource",

test/unit/rules/functions/test_getatt_format.py

@@ -12,6 +12,7 @@
 @pytest.fixture(scope="module")
 def rule():
     rule = GetAttFormat()
+    rule._exceptions = ["AWS::EC2::SecurityGroup.Id"]
     yield rule
 
 
@@ -62,7 +63,7 @@ def template():
         (
             "Valid GetAtt because of exception",
             ["MyBucket", "Arn"],
-            {"format": "AWS::EC2::SecurityGroup.GroupId"},
+            {"format": "AWS::EC2::SecurityGroup.Id"},
             [],
         ),
         (