Make github org comparison case-insensitive, but return original case

Co-authored-by: Joshua Casey <joshuatcasey@gmail.com>

internal/setutil/setutil_test.go

@@ -0,0 +1,34 @@
+// Copyright 2024 the Pinniped contributors. All Rights Reserved.
+// SPDX-License-Identifier: Apache-2.0
+
+package setutil
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestCaseInsensitiveSet(t *testing.T) {
+	var nilSet *CaseInsensitiveSet
+	require.True(t, nilSet.Empty())
+	require.False(t, nilSet.HasAnyIgnoringCase([]string{"a", "b"}))
+	require.False(t, nilSet.HasAnyIgnoringCase(nil))
+	require.False(t, nilSet.ContainsIgnoringCase("a"))
+	require.False(t, nilSet.ContainsIgnoringCase("a"))
+
+	emptySet := NewCaseInsensitiveSet()
+	require.True(t, emptySet.Empty())
+	require.False(t, emptySet.HasAnyIgnoringCase([]string{"a", "b"}))
+	require.False(t, emptySet.HasAnyIgnoringCase(nil))
+	require.False(t, emptySet.ContainsIgnoringCase("a"))
+	require.False(t, emptySet.ContainsIgnoringCase("a"))
+
+	set := NewCaseInsensitiveSet("A", "B", "c")
+	require.False(t, set.Empty())
+	require.False(t, set.HasAnyIgnoringCase([]string{"x", "y"}))
+	require.True(t, set.HasAnyIgnoringCase([]string{"a", "x"}))
+	require.False(t, set.HasAnyIgnoringCase(nil))
+	require.False(t, set.ContainsIgnoringCase("x"))
+	require.True(t, set.ContainsIgnoringCase("a"))
+}