Allow constructing integer types from the factory method with string …

…integers. The integer type already allows it, as that's how ints of arbitrary size over the PHP int max are represented.

src/FreeDSx/Asn1/Asn1.php

@@ -67,10 +67,10 @@ public static function sequenceOf(AbstractType ...$types): SequenceOfType
     }
 
     /**
-     * @param int $int
+     * @param int|string $int
      * @return IntegerType
      */
-    public static function integer(int $int): IntegerType
+    public static function integer($int): IntegerType
     {
         return new IntegerType($int);
     }

tests/spec/FreeDSx/Asn1/Asn1Spec.php

@@ -66,6 +66,12 @@ public function it_should_construct_an_integer_type()
         $this::integer(1)->shouldBeLike(new IntegerType(1));
     }
 
+    public function it_should_construct_an_integer_type_from_a_numeric_string(): void
+    {
+        $this::integer('99999999999999999')
+            ->shouldBeLike(new IntegerType('99999999999999999'));
+    }
+
     public function it_should_construct_an_enumerated_type()
     {
         $this::enumerated(1)->shouldBeLike(new EnumeratedType(1));