Add test cases to TestEmit in attribute (#7751)

Add test cases for `Key.Emit()` values:

- `BoolSliceValue`
- `IntValue`
- `IntSliceValue`

---------

Co-authored-by: Tyler Yahn <MrAlias@users.noreply.github.com>

attribute/key_test.go

@@ -63,6 +63,11 @@ func TestEmit(t *testing.T) {
 			v:    attribute.BoolValue(true),
 			want: "true",
 		},
+		{
+			name: `test Key.Emit() can emit a string representing self.BOOLSLICE`,
+			v:    attribute.BoolSliceValue([]bool{true, false, true}),
+			want: `[true false true]`,
+		},
 		{
 			name: `test Key.Emit() can emit a string representing self.INT64SLICE`,
 			v:    attribute.Int64SliceValue([]int64{1, 42}),
@@ -73,6 +78,16 @@ func TestEmit(t *testing.T) {
 			v:    attribute.Int64Value(42),
 			want: "42",
 		},
+		{
+			name: `test Key.Emit() can representing an int value`,
+			v:    attribute.IntValue(7),
+			want: "7",
+		},
+		{
+			name: `test Key.Emit() can represent an []int value`,
+			v:    attribute.IntSliceValue([]int{1, 2, 3}),
+			want: `[1,2,3]`,
+		},
 		{
 			name: `test Key.Emit() can emit a string representing self.FLOAT64SLICE`,
 			v:    attribute.Float64SliceValue([]float64{1.0, 42.5}),