Fix gosec overflow alerts (#5799)

To allow the golangci-lint upgrade in #5796.

---------

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

log/keyvalue.go

@@ -76,7 +76,8 @@ func IntValue(v int) Value { return Int64Value(int64(v)) }
 
 // Int64Value returns a [Value] for an int64.
 func Int64Value(v int64) Value {
-	return Value{num: uint64(v), any: KindInt64}
+	// This can be later converted back to int64 (overflow not checked).
+	return Value{num: uint64(v), any: KindInt64} // nolint:gosec
 }
 
 // Float64Value returns a [Value] for a float64.

log/keyvalue_test.go

@@ -47,6 +47,7 @@ func TestValueEqual(t *testing.T) {
 		{},
 		log.Int64Value(1),
 		log.Int64Value(2),
+		log.Int64Value(-2),
 		log.Float64Value(3.5),
 		log.Float64Value(3.7),
 		log.BoolValue(true),