gb: add platinum jubilee changes for 2022

Fixes #89

v2/gb/gb_holidays.go

@@ -58,6 +58,29 @@ var (
 		Weekday: time.Monday,
 		Offset:  -1,
 		Func:    cal.CalcWeekdayOffset,
+		Except:  []int{2022},
+	}
+
+	// SpringHoliday2022 represents Spring Bank Holiday in 2022 only on 2-Jun
+	SpringHoliday2022 = &cal.Holiday{
+		Name:      "Spring Bank Holiday",
+		Type:      cal.ObservanceBank,
+		Month:     time.June,
+		Day:       2,
+		Func:      cal.CalcDayOfMonth,
+		StartYear: 2022,
+		EndYear:   2022,
+	}
+
+	// PlatinumJubilee represents Platinum Jubilee Bank Holiday in 2022 only on 3-Jun
+	PlatinumJubilee = &cal.Holiday{
+		Name:      "Platinum Jubilee Bank Holiday",
+		Type:      cal.ObservanceBank,
+		Month:     time.June,
+		Day:       3,
+		Func:      cal.CalcDayOfMonth,
+		StartYear: 2022,
+		EndYear:   2022,
 	}
 
 	// SummerHolidayScotland represents Summer Bank Holiday in Scotland on the first Monday of August
@@ -98,6 +121,8 @@ var (
 		EarlyMay,
 		VEDay,
 		SpringHoliday,
+		SpringHoliday2022,
+		PlatinumJubilee,
 		SummerHoliday,
 		ChristmasDay,
 		BoxingDay,

v2/gb/gb_holidays_test.go

@@ -72,7 +72,16 @@ func TestHolidays(t *testing.T) {
 		{SpringHoliday, 2019, d(2019, 5, 27), d(2019, 5, 27)},
 		{SpringHoliday, 2020, d(2020, 5, 25), d(2020, 5, 25)},
 		{SpringHoliday, 2021, d(2021, 5, 31), d(2021, 5, 31)},
-		{SpringHoliday, 2022, d(2022, 5, 30), d(2022, 5, 30)},
+		{SpringHoliday, 2022, time.Time{}, time.Time{}},
+		{SpringHoliday, 2023, d(2023, 5, 29), d(2023, 5, 29)},
+
+		{SpringHoliday2022, 2021, time.Time{}, time.Time{}},
+		{SpringHoliday2022, 2022, d(2022, 6, 2), d(2022, 6, 2)},
+		{SpringHoliday2022, 2023, time.Time{}, time.Time{}},
+
+		{PlatinumJubilee, 2021, time.Time{}, time.Time{}},
+		{PlatinumJubilee, 2022, d(2022, 6, 3), d(2022, 6, 3)},
+		{PlatinumJubilee, 2023, time.Time{}, time.Time{}},
 
 		{SummerHolidayScotland, 2015, d(2015, 8, 3), d(2015, 8, 3)},
 		{SummerHolidayScotland, 2016, d(2016, 8, 1), d(2016, 8, 1)},