fix: use golang.org/x/exp/constraints (#12)

The constraints builtin has been removed as per
[this issue](golang/go#50792).

Author: mtoohey31

scripts/gen/tuple.tpl

@@ -2,7 +2,7 @@ package tuple
 
 import (
 	"fmt"
-	"constraints"
+	"golang.org/x/exp/constraints"
 )
 
 {{/* $typeRef can be used when the context of dot changes. */}}

tuple1.go

@@ -1,8 +1,8 @@
 package tuple
 
 import (
-	"constraints"
 	"fmt"
+	"golang.org/x/exp/constraints"
 )
 
 // T1 is a tuple type holding 1 generic values.

tuple2.go

@@ -1,8 +1,8 @@
 package tuple
 
 import (
-	"constraints"
 	"fmt"
+	"golang.org/x/exp/constraints"
 )
 
 // T2 is a tuple type holding 2 generic values.

tuple3.go

@@ -1,8 +1,8 @@
 package tuple
 
 import (
-	"constraints"
 	"fmt"
+	"golang.org/x/exp/constraints"
 )
 
 // T3 is a tuple type holding 3 generic values.

tuple4.go

@@ -1,8 +1,8 @@
 package tuple
 
 import (
-	"constraints"
 	"fmt"
+	"golang.org/x/exp/constraints"
 )
 
 // T4 is a tuple type holding 4 generic values.

tuple5.go

@@ -1,8 +1,8 @@
 package tuple
 
 import (
-	"constraints"
 	"fmt"
+	"golang.org/x/exp/constraints"
 )
 
 // T5 is a tuple type holding 5 generic values.

tuple6.go

@@ -1,8 +1,8 @@
 package tuple
 
 import (
-	"constraints"
 	"fmt"
+	"golang.org/x/exp/constraints"
 )
 
 // T6 is a tuple type holding 6 generic values.

tuple7.go

@@ -1,8 +1,8 @@
 package tuple
 
 import (
-	"constraints"
 	"fmt"
+	"golang.org/x/exp/constraints"
 )
 
 // T7 is a tuple type holding 7 generic values.

tuple8.go

@@ -1,8 +1,8 @@
 package tuple
 
 import (
-	"constraints"
 	"fmt"
+	"golang.org/x/exp/constraints"
 )
 
 // T8 is a tuple type holding 8 generic values.

tuple9.go

@@ -1,8 +1,8 @@
 package tuple
 
 import (
-	"constraints"
 	"fmt"
+	"golang.org/x/exp/constraints"
 )
 
 // T9 is a tuple type holding 9 generic values.