[#3532] bring AUTHORS and ChangeLog up to date

Author: andrei-pavel

AUTHORS

@@ -267,4 +267,4 @@ We have received the following contributions:
    2023-02: Fixed several examples in DHCPv6 section of the ARM.
 
  - Dimitry Andric
-   2024-08: Added support for libc++ 19 and later.
+   2024-09: Added support for libc++ 19 and later.

ChangeLog

@@ -1,12 +1,12 @@
-Kea 2.7.2 (development) released on August 28, 2024
-
 2278.	[build]		dim
 	Replace ``std::basic_string<uint8_t>`` with equivalent
 	``std::vector<uint8_t>`` constructs, since the former has been
 	deprecated for a while in libc++, and has been completely
 	removed as of libc++ 19.
 	(Gitlab #3532)
 
+Kea 2.7.2 (development) released on August 28, 2024
+
 2277.	[build]		andrei
 	"libca_rbac.so" is now a symbolic link to "libdhcp_rbac.so".
 	(Gitlab #3550)