v1.6.0 to fix memory leak bugs, etc.

### Release v1.6.0

1. Fix memory leak bugs. Check [memory leak on 'server_version' #17](#17) and [memory leak on MySQL_Connection.MySQL_Packet.buffer #18](#18)
2. Optimize library code by using `reference-passing` instead of `value-passing`
3. Update RP2040 Ethernet-related examples to use the same SS/CS pin GP17 for [ArduinoCore-mbed mbed_rp2040 core](https://github.com/arduino/ArduinoCore-mbed) as [arduino-pico rp2040 core](https://github.com/earlephilhower/arduino-pico)
4. Update `Packages' Patches`

Author: khoih-prog

README.md

@@ -1929,9 +1929,11 @@ Submit issues to: [MySQL_MariaDB_Generic issues](https://github.com/khoih-prog/M
 1. Based on and modified from [Dr. Charles Bell's MySQL_Connector_Arduino Library](https://github.com/ChuckBell/MySQL_Connector_Arduino)
 2. Thanks to good work of [Miguel Alexandre Wisintainer](https://github.com/tcpipchip) for initiating, inspriring, working with, developing, debugging and testing.
 3. Thanks to [graham999au](https://github.com/graham999au) for the enhanement request [**NativeEthernet support for Teensy 4.1** #8](https://github.com/khoih-prog/MySQL_MariaDB_Generic/issues/8), and help testing, leading to new version v1.3.0
-4. Thanks to [Pablo Martikian](https://github.com/pabloandresm) to report issues
+4. Thanks to [Pablo Martikian](https://github.com/pabloandresm) to report issues:
+
 	- [memory leak on 'server_version' #17](https://github.com/khoih-prog/MySQL_MariaDB_Generic/issues/17)
 	- [memory leak on MySQL_Connection.MySQL_Packet.buffer #18](https://github.com/khoih-prog/MySQL_MariaDB_Generic/issues/18)
+
 leading to version v1.6.0 to fix memory leak bugs.
 
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