Document possible values of schema fields (#455)

* Document possible values of schema fields

* Change from possible to supported

stackit/internal/utils/utils_test.go

@@ -192,3 +192,36 @@ func TestSimplifyBackupSchedule(t *testing.T) {
 		})
 	}
 }
+
+func TestSupportedValuesDocumentation(t *testing.T) {
+	tests := []struct {
+		description string
+		values      []string
+		expected    string
+	}{
+		{
+			"empty values",
+			[]string{},
+			"",
+		},
+		{
+			"single value",
+			[]string{"value"},
+			"Supported values are: `value`.",
+		},
+		{
+			"multiple values",
+			[]string{"value1", "value2", "value3"},
+			"Supported values are: `value1`, `value2`, `value3`.",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.description, func(t *testing.T) {
+			output := SupportedValuesDocumentation(tt.values)
+			if output != tt.expected {
+				t.Fatalf("Data does not match: %s", output)
+			}
+		})
+	}
+}